Method for processing additional information related to an announced service or content in an NRT service and a broadcast receiver

ABSTRACT

A method of processing additional information related to an announced service or content in a Non-Real Time (NRT) service and the broadcast receiver are disclosed herein. A method of providing a Non-Real Time (NRT) service in a broadcasting receiver includes receiving a service map table (SMT) and a first descriptor through a service signaling channel, identifying an image identifier and an image type of an image for an NRT service based upon the first descriptor, receiving the image via a flute session and displaying the image when corresponding service is played, wherein the image is logo or icon data for the NRT service. The method may further include connecting a service signaling channel, parsing the received SMT and the first descriptor, determining whether a service is the NRT service based upon the parsed SMT and storing the received image.

This application is a continuation of prior application Ser. No.13/775,851 filed Feb. 25, 2013, which is a continuation of priorapplication Ser. No. 12/461,732 filed Aug. 21, 2009 (now issued as U.S.Pat. No. 8,407,743), which claims the benefit of U.S. ProvisionalApplication No. 61/121,178, filed on Dec. 9, 2008, which is herebyincorporated by reference. Also, this application claims the benefit ofU.S. Provisional Application No. 61/138,494, filed on Dec. 17, 2008,which is hereby incorporated by reference. This application also claimsthe benefit of U.S. Provisional Application No. 61/153,973, filed onFeb. 20, 2009, which is hereby incorporated by reference. Thisapplication also claims the benefit of U.S. Provisional Application No.61/153,985, filed on Feb. 20, 2009, which is hereby incorporated byreference. And this application claims the priority benefit of KoreanApplication No. 10-2008-0082584, filed on Aug. 22, 2008, which is herebyincorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for processing additionalinformation related to an announced service or content in a Non-RealTime (NRT) service and a broadcast receiver.

2. Discussion of the Related Art

Generally, a Non-Real Time (NRT) service is one of powerful applicationsthat will be utilized for future DTV services. The NRT is accompanied bynon-real time transmission (not real-time streaming), storage andviewing operations and transmits a content of a file type on a surplusbandwidth via a broadcast medium such as terrestrial and the like. And,it is expected that the NRT will be implemented various kinds of servicefunctions including push VOD, targeted advertising and the like.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a broadcast receiverand a method of processing additional information related to anannounced service or content in a Non-Real Time (NRT) service thatsubstantially obviate one or more problems due to limitations anddisadvantages of the related art.

An object of the present invention is to provide a broadcast receiverand a method of mapping signaling information to announcementinformation, wherein the signaling data for an NRT service can bedefined.

Another object of the present invention is to provide a broadcastreceiver and a method of mapping signaling information to announcementinformation, wherein a scheme for transmitting the above-definedsignaling data can be defined.

Another object of the present invention is to provide a broadcastreceiver and a method of mapping signaling information to announcementinformation, wherein an NRT service is accessible in a manner that thereceiver receives and process signaling data for the transmitted NRTservice.

Another object of the present invention is to provide a method ofmapping a content identifier of the signaling data to an identifier of aselected and transmitted content in a receiver.

Another object of the present invention is to provide a method ofreceiving and processing a content selected from a service guideconfigured by using the signaling data in the receiver, which canprovide the processed content to a user.

A further object of the present invention is to provide a method ofprocessing additional information related to an announced service orcontent in the NRT service, which can provide the processed theadditional information related to the announced service or content to auser.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, amethod of providing a Non-Real Time (NRT) service in a broadcastingreceiver includes receiving a service map table (SMT) and a firstdescriptor through a service signaling channel, identifying an imageidentifier and an image type of an image for an NRT service based uponthe first descriptor, receiving the image via a flute session anddisplaying the image when corresponding service is played, wherein theimage is logo or icon data for the NRT service.

The method may further include connecting a service signaling channel,parsing the received SMT and the first descriptor, determining whether aservice is the NRT service based upon the parsed SMT and storing thereceived image.

The NRT service may include a mobile NRT service.

The descriptor may be included in the service level descriptor loop ofthe SMT.

The descriptor may include a first field identifying an address toreceive the image.

The image type of the image may include at least one of images like abroadcaster logo, a channel change image, a channel logo, a backgroundimage, and further includes at least one of image format like a JPG, aGIF and a BMP.

The additional information may be identified based upon a contentidentifier related to the image.

The flute session may be accessed based upon any one of the received SMTand the received first descriptor.

In another aspect of the present invention, a method of providing aNon-Real Time (NRT) service in a broadcasting receiver includesreceiving a first signaling information, parsing a descriptor includinguniform resource locator (URL) information referencing a content or aservice based upon the first signaling information, accessing the URLinformation and receiving additional information related to the contentor the service.

The method may further comprise storing the received additionalinformation related to corresponding content.

The method may further comprise determining whether the descriptor isincluded in the parsed first signaling information.

The NRT service may include a fixed NRT service.

The first signaling information may include an NRT content table (NCT).

The descriptor may be included in the content level descriptor loop ofthe NCT.

The additional information is at least one of an additional logo image,an additional poster and an additional file related to the announcedcontent.

In another aspect of the present invention, a broadcasting receiverincludes a receiving unit for receiving a service map table (SMT) and afirst descriptor through a service signaling channel, a controller forcontrolling to determine whether a service is the NRT service based uponthe parsed SMT and identify an image identifier and an image type of animage for a Nor-Real Time (NRT) service based upon the first descriptor,an accessing unit for receiving the image via a flute session and adisplay unit for displaying the image when corresponding service isplayed, wherein the image is logo or icon data for the NRT service.

The broadcasting receiver may further comprise a storage unit forstoring the received image.

The controller controls to identify an address to receive the image.

In another aspect of the present invention, a broadcasting receiverincludes a first receiving unit for receiving a first signalinginformation, a controller for controlling to parse a descriptorincluding uniform resource locator (URL) information referencing acontent or a service based upon the parsed first signaling information,an accessing unit for accessing the URL information, a second receivingunit for receiving additional information related to the content or theservice and a display unit for outputting the received additionalinformation in connection with the corresponding content.

The broadcasting receiver may further comprises a storage unit forreceiving the received the additional information.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings;

FIG. 1 is an exemplary conceptional diagram of an NRT service;

FIG. 2 is an exemplary diagram explaining relations between an NRTservice, content items and files;

FIG. 3 is a diagram for a protocol stack of a fixed NRT serviceconfigured according to an embodiment of the present invention;

FIG. 4 is a block diagram of a receiving system according to anembodiment of the present invention;

FIG. 5 is a diagram for a bit-stream section of a TVCT sectionconfigured according to an embodiment of the present invention;

FIG. 6 is an exemplary diagram of an ATSC service type according to thepresent invention;

FIG. 7 is another exemplary diagram of an ATSC service type according tothe present invention;

FIG. 8 is a diagram for a bit-stream syntax of a DST section to identityan NRT application configured according to an embodiment of the presentinvention;

FIG. 9 is a diagram for a signaling method in case of transmitting anNRT service through an ATSC broadcasting system according to anotherembodiment of the present invention;

FIG. 10 is a flowchart for FIG. 9;

FIGS. 11 and 12 are diagrams for a bit-stream syntax of NST extracted bya receiver from a received MPEG-2 TS configured according to oneembodiment of the present invention;

FIG. 13 is a diagram for a bit-stream syntax ofNRT_component_descriptor( ) configured according to one embodiment ofthe present invention;

FIG. 14 is a diagram for a bit-stream syntax ofNRT_component_data_descriptor for FLUTE file delivery configuredaccording to one embodiment of the present invention;

FIG. 15 is a diagram for a bit-stream syntax of an NCT sectionconfigured according to one embodiment of the present invention;

FIG. 16 is a diagram for an NRT service signaling structure configuredaccording to another embodiment of the present invention;

FIG. 17 is a diagram for a bit-stream syntax of an NRT content deliverychannel details descriptor configured according to one embodiment of thepresent invention;

FIG. 18 is a diagram for a protocol stack of a mobile NRT serviceconfigured according to one embodiment of the present invention;

FIG. 19 is an exemplary block diagram showing the configuration of areception system according to an embodiment of the present invention;

FIG. 20 is a view showing an embodiment of the structure of a data groupaccording to the present invention;

FIG. 21 is a view showing the structure of an RS frame containing amobile NRT service configured according to an embodiment of the presentinvention;

FIG. 22 is a view showing an example of an M/H frame structure fortransmission or reception of mobile service data according to thepresent invention;

FIG. 23 is a view showing a data transmission structure in a physicallayer according to an embodiment of the present invention;

FIGS. 24 and 25 are views showing the bitstream syntax of an SMTconfigured according to an embodiment of the present invention;

FIG. 26 is a view explaining a relationship among an M/H service, aFLUTE session and an NRT service according to the present invention;

FIG. 27 is an exemplary diagram for a bit-stream syntax of a descriptorincluded the SMT according to the present invention;

FIG. 28 is an exemplary diagram for field information related to thedownload_image_type field;

FIG. 29 is an exemplary diagram for specifying the download_path_typefield and the download_path field according to the present invention;

FIG. 30 is an exemplary diagram for representing a download path of animage downloaded through a FLUTE session according to the presentinvention;

FIG. 31 is an exemplary flowchart for processing additional informationrelated to an announced service or an announced content included the NRTservice according to the present invention;

FIG. 32 is an exemplary flowchart for processing additional informationrelated to an announced content included the NRT service according tothe present invention; and

FIGS. 33 and 34 is an exemplary diagram being displayed logo related tothe received service or content according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

Definitions of Terminologies Used for the Invention

Terminologies used for the present invention are selected from generalterminologies, which are currently and widely used, in consideration offunctions in the present invention but may vary according to intentionsof a person having an ordinary knowledge in the technical field,practices or the advent of new technology, etc. In specific case, aterminology may be arbitrarily chosen by the applicant(s). In this case,its detailed meaning shall be described in Detailed Description ofInvention. Therefore, the terminology used for the present inventionneeds to be defined based on the intrinsic meaning of the terminologyand the contents across the present invention instead of a simple nameof the terminology.

A real time (RT) service among terminologies used for the presentinvention means a real-time service as it is. On the contrary, anon-real time (NRT) service means a non-real time service that is notbind on time except the RT service.

Among the terms used in the description of the present invention, mainservice data correspond to data that can be received by a fixedreceiving system and may include audio/video (A/V) data. Morespecifically, the main service data may include A/V data of highdefinition (HD) or standard definition (SD) levels and may also includediverse data types required for data broadcasting. Also, the known datacorrespond to data pre-known in accordance with a pre-arranged agreementbetween the receiving system and the transmitting system.

Additionally, among the terms used in the present invention, “M/H” (orMH) corresponds to the initials of “mobile” and “handheld” andrepresents the opposite concept of a fixed-type system. Furthermore, theM/H service data may include at least one of mobile service data, andhandheld service data, and will also be referred to as “mobile servicedata” for simplicity. Thereafter, the M/H, MH, and mobile are used asthe same meaning. Herein, the mobile service data not only correspond toM/H service data but may also include any type of service data withmobile or portable characteristics. Therefore, the mobile service dataaccording to the present invention are not limited only to the M/Hservice data.

The above-described mobile service data may correspond to data havinginformation, such as program execution files, stock information, and soon, and may also correspond to A/V data. Most particularly, the mobileservice data may correspond to A/V data having lower resolution andlower data rate as compared to the main service data. For example, if anA/V codec that is used for a conventional main service corresponds to aMPEG-2 codec, a MPEG-4 advanced video coding (AVC) or scalable videocoding (SVC) having better image compression efficiency may be used asthe A/V codec for the mobile service. Furthermore, any type of data maybe transmitted as the mobile service data. For example, transportprotocol expert group (TPEG) data for broadcasting real-timetransportation information or non-real time (NRT) service data may betransmitted as the main service data.

Also, a data service using the mobile service data may include weatherforecast services, traffic information services, stock informationservices, viewer participation quiz programs, real-time polls andsurveys, interactive education broadcast programs, gaming services,services providing information on synopsis, character, background music,and filming sites of soap operas or series, services providinginformation on past match scores and player profiles and achievements,and services providing information on product information and programsclassified by service, medium, time, and theme enabling purchase ordersto be processed. Herein, the present invention is not limited only tothe services mentioned above.

A transmission system of the present invention can multiplex andtransmit mobile service data containing an NRT service and main servicedata in the same or different physical channels, without influencing thereception of main service data by an existing reception system (backwardcompatibility).

Furthermore, the transmitting system according to the present inventionperforms additional encoding on the mobile service data and inserts thedata already known by the receiving system and transmitting system(e.g., known data), thereby transmitting the processed data.

Therefore, when using the transmitting system according to the presentinvention, the receiving system may receive the mobile service dataduring a mobile state and may also receive the mobile service dataincluding an NRT service with stability despite various distortion andnoise occurring within the channel.

A Conceptional Diagram of an NRT Service

FIG. 1 is an exemplary conceptional diagram for an NRT service.

First of all, a broadcasting station transmits an RT (real time) serviceaccording to a conventional method. In doing so, the broadcastingstation transmits the RT service or an NRT (non-real time) service usinga bandwidth left in the due course. In this case, the NRT service cancontain a news clip, weather information, advertisements, content forPush VOD (video on demand) and the like.

Yet, a related art DTV receiver, i.e., a legacy device has the principlethat the operation is not affected by an NRT stream included within achannel. However, the related art DTV receiver has a problem inreceiving and processing an NRT service provided by a broadcastingstation properly because of not having a means for processing unit forthe NRT service.

On the contrary, a broadcast receiver according to the presentinvention, i.e., an NRT device is able to properly receive and processan NRT service combined with an RT service, thereby providing a viewerwith more various functions than those of the related art DTV.

In this case, the RT service and the NRT service are transmitted on thesame DTV channel or different DTV channels and are transmitted throughan MPEG-2 transport packet (TP) or an internet protocol (IP) datagram.Hence, a receiver needs to identify the two kinds of servicestransmitted on the same or different channel. For this, thisspecification discloses a method of defining and providing signalinginformation to enable a receiver to receive and process an NRT serviceproperly. In this case, a broadcasting station provides signalinginformation. Specifically, at least one unique packet identifier (PID)for identifying an NRT service can be allocated.

A Description for Relations Among NRT Service, Content Item and File

FIG. 2 is an exemplary diagram to explain relations among an NRTservice, content items and files.

Referring to FIG. 2, an NRT service can include one or more contentitems. And, each of the content items can include one or more files.And, each of the content items is an independently playable entity andmay correspond to a program or an event in a real time broadcast.Therefore, the NRT service means a group that is serviceable with acombination of the above content items. And, the NRT service correspondsto a channel concept in real time.

In order for a receiver to properly process the above NRT service,signaling for the corresponding NRT service is required. The presentinvention intends to properly process an NRT service received by areceiver by defining and providing the signaling information. Besides,details of the signaling information shall be described in thedescription of the corresponding part.

First of all, NRT services can be mainly categorized into a fixed NRTservice and a mobile NRT service according to a type of acquiring an IPdatagram. In the following description, the fixed NRT service and themobile NRT service are sequentially specified for clarity andconvenience of explanation.

A Protocol for a Fixed NRT Service

FIG. 3 is a diagram for a protocol stack of a fixed NRT serviceconfigured according to one embodiment of the present invention.

Referring to FIG. 3, a protocol stack for providing a fixed NRT servicetransmits NRT content items/files, IP datagram including a signalingchannel for providing NST and NCT and PSI/PSIP data using an MPEG-2 TSformat.

In FIG. 3, the fixed NRT service is packetized according to UDP in an IPlayer. The UDP packet becomes UDP/IP packet data by being packetizedagain according to an IP scheme. In this disclosure, the packetizedUDP/IP packet data is named an IP datagram for clarity and convenience.

The NRT content items/files are packetized according to FLUTE scheme orALC/LCT scheme. The ALC/LCT packet is transported by being encapsulatedin a UDP datagram. The ALC/LCT/UDP packet is packetized intoALC/LCT/UDP/IP packet according to IP datagram scheme to become an IPdatagram. This IP datagram is contained in MPEG-2 TS through DSM-CCaddressable sections for transport. In this case, the ALC/LCT/UDP/IPpacket is the information on FLUTE session and includes a FDT as well.

A signaling information channel including an NST and an NCT ispacketized according to a UDP scheme. This UDP packet is packetizedaccording to an IP scheme again to become UDP/IP packet data, i.e., IPdatagram. This IP datagram is also contained in the MPEG-2 TS throughthe DSM-CC addressable sections for transport.

And, a PSI/PSIP table is separately defined and contained in the MPEG-2TS.

The MPEG-2 TS containing the above described NRT content items/files,signaling information channel and PSI/PSIP data therein are transferredby being modulated by a predetermined transmission scheme such as VSBtransmission scheme.

A Receiving System

FIG. 4 is a block diagram of a receiving system according to oneembodiment of the present invention.

Referring to FIG. 4, the receiving system mainly includes a part of abaseband processor, a part of an MPEG-2 service demultiplexer (demux), apart of a stream component handler, a part of a media handler, a part ofa file handler and other parts. The units of the receiving system shownin FIG. 4 are explained as follows.

First of all, the part of the baseband processor includes a tuner 201and a vestigial side band (VSB) demodulator 202. The tuner 201 detectsVSB radio frequency (RF) signal transmitted over the air and thenextracts a symbol from the detected VSB RF signal. In this case, thetuner 201 is controlled by a service manager 228. The VSB demodulator202 reconstructs meaningful data by demodulating the VSB symbolextracted by the tuner 201.

The part of the MPEG-2 service demultiplexer includes an MPEG-2 TPbuffer/parser 203, a program specific information/program and systeminformation protocol (PSI/PSIP) section/buffer 204, a descrambler 205,an MPEG-2 TP demultiplexer (demux) 206 and a personal video recorder(PVR) storage 207.

The MPEG-2 TP buffer/parser 203 buffers and reconstructs an MPEG-2 TPcarried on a VSB signal and then detects and processes a TP header.

The PSI/PSIP section/buffer 204 buffers and parses PSI/PSIP section datacarried on an MPEG-2 TS. In this case, the parsed PSI/PSIP data iscollected by the service manager 228 and is then stored as a service mapand guide data in a database.

The descrambler 205 reconstructs data of a payload for a scrambledpacket payload in the MPEG-2 TP using an encryption key or the likedelivered from a conditional access (CA) stream handler 216.

The MPEG-2 TP demultiplexer 206 filters off an MPEG-2 TP varied on a VSBsignal or a TP, which is attempted to be processed by the receiver,among the MPEG-2 TP stored in the PVR storage 207 and then relays thefiltered TP to a proper processing module. In this case, the MPEG-2 TPdemultiplexer 206 can be controlled by the service manager 228 and thePVR manager 235.

The PVR storage 207 stores the received MPEG-2 TP using the VSB signalaccording to a request made by a user and then outputs the MPEG-2 TPaccording to a request made by a user. In this case, the PVR storage 207can be controlled by the PVR manager 235.

The part of the stream component handler includes a packetizedelementary stream (PES) buffer/handler 208, an elementary stream (ES)buffer/handler 209, a program clock reference (PCR) handler 210, asystem time clock (STC) unit 211, a digital storage media command andcontrol (DSM-CC) section buffer/handler 212, an IP datagrambuffer/header parser 213, a user datagram protocol (UDP) datagrambuffer/handler 213, a CA stream buffer/handler 214 and a servicesignaling section buffer/handler 215.

The PES buffer/handler 208 buffers and reconstructs a PES carried on anMPEG-2 TS.

The ES buffer/handler 208 buffers and reconstructs an ES such as audiodata, video data or the like, which is transmitted as a PES, and thendelivers the reconstructed ES to a proper A/V decoder 218.

The PCR handler 210 handles PCR data used for time synchronization ofaudio and video streams or the like.

The STC unit 211 corrects a clock value of the A/V decoder 218 using areference clock value delivered via the PCR handler 210 to enable timesynchronization.

The DSM-CC section buffer/handler 212 buffers and handles DSM-CC sectiondata for a file transmission via the MPEG-2 TP, an IP datagramencapsulation or the like.

The IP datagram buffer/header parser 213 buffers and reconstructs an IPdatagram, which is encapsulated via DSM-CC addressable section and isthen carried on an MPEG-2 TP. The IP datagram buffer/header parser 213parses a header of each IP datagram through the reconstruction. In thiscase, the IP datagram buffer/header parser 213 is controlled by theservice manager 228.

If scrambling is applied to a payload in the received IP datagram, thedescrambler 214 reconstructs data of the payload using an encryption keyfor the payload or the like delivered from the CA stream handler 216.

The UDP datagram buffer/handler 215 buffers and reconstructs a UDPdatagram carried on an IP datagram and also parses and processes a UDPheader.

The CA stream buffer/handler 216 buffers and handles such data as a keyvalue for descrambling, e.g., an entitlement management message (EMM)transmitted for a conditional access function carried on an MPEG-2 TS oran IP stream, an entitlement control message (ECM) and the like. In thiscase, an output of the CA stream buffer/handler 216 is delivered to thedescrambler 214 to perform a decryption operation of an MPEG-2 TP or anIP datagram that carries AV data, file data and the like.

The service signaling section buffer/parser 217 processes an NRT ServiceTable (NST), an NRT Content Table (NCT) and descriptors related to theNST or the NCT for signaling an NRT service of the present invention,which will be explained later. The processed signaling information istransferred to the NRT service manager 229.

The part of the media handler is explained as follows. First of all, thepart of the media handler includes A/V decoders 218.

The AV decoders 218 decode compressions of audio and vide data deliveredvia the ES handler 209 and then processes the decoded data, which are tobe presented to a user.

The part of the file handler is explained as follows. First of all, thepart of the filer handler mainly includes an Asynchronous LayeredCoding/Layered Coding Transport (ALC/CLT) buffer/parser 219, a filedescription table (FDT) handler 220, an extensible markup language (XML)parser 221, a file reconstruction buffer 222 and a decompressor 223.

The ALC/LCT buffer/parser 219 buffers and reconstructs ALC/LCT datacarried on UDP/IP stream and then parses a header of ALC/LCT and aheader extension thereof. In this case, the ALC/LCT buffer/parser 219can be controlled by the NRT service manager 229.

The FDT handler 220 parses and processes a FDT of a File Delivery overUnidirectional Transport (FLUTE) protocol transmitted via an ALC/LCTsession. It is able to transfer the processed FDT to the NRT servicemanager 229. In this case, the FDT handler 220 can be controlled by theNRT service manager 229.

The XML parser 221 parses an XML document transmitted via the ALC/LCTsession and then delivers the parsed data to such a proper module as theFDT handler 220, the SG handler 227 and the like.

The file reconstruction buffer 222 reconstructs a file transferred tothe ALC/LCT and FLUTE session.

If the file transferred to the ALC/LCT and FLUTE session is compressed,the decompressor 223 performs a process for decompressing thecompression.

The file decoder 224 decodes a file reconstructed by the filereconstruction buffer, a file decompressed by the decompressor 223 or afile extracted from the file storage 225.

The file storage 225 stores and extracts the received file. In thiscase, the received file may contain NRT content.

Finally, the remaining parts except for the above-described units areexplained as follows.

First of all, a middleware (M/W) engine 226 processes data of a filethat is not an AV stream transferred via a DSM-CC section, an IP diagramand the like and then delivers the processed data to the presentationmanager 234.

The SG handler 227 collects and parses service guide data transferred inan XML document format and then delivers the parsed data to the EPGmanager 230.

The service manager 228 produces a service map by collecting and parsingPSI/PSIP data carried on MPEG-2 TS and service signaling section datacarried on an IP stream and then controls an access to a servicespecified by a user by storing the service map in a service map & guidedatabase. In this case, the service manager 228 is controlled by anoperation controller 230 and then controls the tuner 201, the MPEG-2 TPdemultiplexer 206, the IP datagram buffer/handler 213, the NRT servicemanager 229 and the like.

The NRT service manager 229 performs overall managements on the NRTservice transferred in an object/file format via FLUTE session on an IPlayer. The NRT service manager 229 parses the signaling informationtransferred from the service signaling section buffer/parser 217. And,the parsed signaling information is transferred to the service map &guide database 236 to be stored therein. Moreover, the NRT servicemanager 229 controls NCT information, which correspond to contentsrelated to a service guide in the signaling information, to betransferred to the EPG manager 230, thereby forming EPG data. In thiscase, the NRT service manager 229 controls the FDT handler 220, the filestorage 225 and the like. Therefore, the NRT service manager 229receives the FDT from the FDT handler 220, parses the received FDT andthen controls received NRT contents to be stored as a hierarchicalstructure in the file storage 225. And, the NRT service manager 229controls the corresponding NRT contents to be extracted from the filestorage 225 in case that a user makes a selection for the NRT service.

The EPG manager 230 receives the service guide data from the SG handler227, configures EPG data, and then controls the EPG data to bedisplayed.

The application manager 231 performs overall managements on processingof application data transferred in such a format as an object, a fileand the like.

The user interface (UI) manager 232 delivers an input of a user via a UIto the operation controller 233 and enables an operation of a processfor a user-requested service to be initiated.

The operation controller 233 processes a user's command delivered viathe UI manager 232 and then enables a manager of a necessary module toperform a corresponding action.

And, the presentation manager 234 provides at least one of A/V dataoutputted from the A/V decoder 218, file data outputted the middleware(M/W) engine 226 and EPG data outputted from the EPG manager 230 to uservia speaker and/or screen.

A Terrestrial Virtual Channel Table (TVCT) Section

FIG. 5 is a diagram for a bit-stream section of a TVCT sectionconfigured according to one embodiment of the present invention.

Referring to FIG. 5, a TVCT section is described as having a tableformat similar to that of an MPEG-2 private section. However, this ismerely exemplary, and the present invention will not be limited to theexample given herein.

The TVCT can be divided into a header, a body and a trailer. The headerpart ranges from table_id field to protocol_version field. And,transport_stream_id field is a 16-bit field and indicates an MPEG-2 TSIDwithin a program association table (PAT) defined by a PID value of ‘0’for multiplexing. In the body part, num_channels_in_section field is an8-bit field and indicates the number of virtual channels within a VCTsection. Finally, the trailer part includes a CRC_(—)32 field.

First of all, the header part is explained as follows.

A table_id field is an 8-bit unsigned integer number that indicates thetype of table section being defined herein. For theterrestrial_virtual_channel_table_section( ), the table_id shall be‘0xC8’.

A section_syntax_indicator is a one-bit field which shall be set to ‘1’for the terrestrial_virtual_channel_table_section( ).

A private_indicator field (1-bit) shall be set to ‘1’.

A section_length is a twelve bit field, the first two bits of whichshall be ‘00’. This field specifies the number of bytes of the section,starting immediately following the section_length field, and includingthe CRC. The value in this field shall not exceed 1021.

A table_id_extension field is set to ‘0x000’.

A version_number field (5-bit) represents the version number of the VCT.For the current VCT (current_next_indicator=‘1’), the version numbershall be incremented by ‘1’ whenever the definition of the current VCTchanges. Upon reaching the value ‘31’, it wraps around to ‘0’. For thenext VCT (current_next_indicator=‘0’), the version number shall be oneunit more than that of the current VCT (also in modulo 32 arithmetic).In any case, the value of the version_number shall be identical to thatof the corresponding entries in the MGT.

A current_next_indicator is a one-bit indicator, which when set to ‘1’indicates that the VCT sent is currently applicable. When the bit is setto ‘0’, it indicates that the table sent is not yet applicable and shallbe the next table to become valid. This standard imposes no requirementthat “next” tables (those with current_next_indicator set to ‘0’) mustbe sent. An update to the currently applicable table shall be signaledby incrementing the version_number field.

A section_number field (8 bit) gives the number of this section. Thesection_number of the first section in the TVCT shall be ‘0x00’. Itshall be incremented by one with each additional section in the TVCT.

A last_section_number field (8 bit) specifies the number of the lastsection (that is, the section with the highest section_number) of thecomplete TVCT.

A protocol_version is an 8-bit unsigned integer field whose function isto allow, in the future, this table type to carry parameters that may bestructured differently than those defined in the current protocol. Atpresent, the only valid value for protocol_version is zero. Non-zerovalues of protocol_version may be used by a future version of thisstandard to indicate structurally different tables.

The body part will now be explained as follows.

A num_channels_in_section field (8-bit) specifies the number of virtualchannels in this VCT section. The number is limited by the sectionlength.

A short name field represents the name of the virtual channel,represented as a sequence of one to seven 16-bit code values.

A major_channel_number field is a 10-bit number that represents the“major” channel number associated with the virtual channel being definedin this iteration of the “for” loop. Each virtual channel shall beassociated with a major and a minor channel number. The major channelnumber, along with the minor channel number, act as the user's referencenumber for the virtual channel. The major_channel_number shall bebetween ‘1’ and ‘999’. The value of major_channel_number shall be setsuch that in no case is a major_channel_number/minor_channel_number pairduplicated within the TVCT.

A minor_channel_number field is a 10-bit number in the range ‘0’ to‘999’ that represents the “minor” or “sub”-channel number. This field,together with major_channel_number, performs as a two-part channelnumber, where minor_channel_number represents the second or right-handpart of the number. When the service_type is analog television,minor_channel_number shall be set to ‘0’. Services whose service_type iseither ATSC_digital_television or ATSC_audio_only shall use minornumbers between ‘1’ and ‘99’. The value of minor_channel_number shall beset such that, in no case, major_channel_number/minor_channel_numberpair is duplicated within the TVCT. For other types of services, such asdata broadcasting, valid minor virtual channel numbers are between ‘1’and ‘999’.

A modulation mode field is an 8-bit unsigned integer number thatindicates the modulation mode for the transmitted carrier associatedwith this virtual channel.

A carrier_frequency field includes the recommended value for these 32bits is zero. Use of this field to identify carrier frequency isallowed, but is deprecated.

A channel_TSID is a 16-bit unsigned integer field in the range ‘0x0000’to ‘0xFFFF’ that represents the MPEG-2 TSID associated with the TScarrying the MPEG-2 program referenced by this virtual_channel.

A program_number field is a 16-bit unsigned integer number thatassociates the virtual_channel being defined here with the MPEG-2PROGRAM ASSOCIATION and TS PROGRAM MAP tables. For virtual channelsrepresenting analog services, a value of ‘0xFFFF’ shall be specified forprogram_number.

An ETM_location is 2-bit field specifies the existence and the locationof an Extended Text Message (ETM).

An access_controlled is a 1-bit Boolean flag that indicates, when set,that the events associated with this virtual channel may be accesscontrolled. When the flag is set to ‘0’, event access is not restricted.

A hidden is a 1-bit Boolean flag that indicates, when set, that thevirtual channel is not accessed by the user by direct entry of thevirtual channel number. Hidden virtual channels are skipped when theuser is channel surfing, and appear as if undefined, if accessed bydirect channel entry. Typical applications for hidden channels are testsignals and NVOD services. Whether a hidden channel and its events mayappear in EPG displays depends on the state of the hide_guide bit.

A hide_guide is a Boolean flag that indicates, when set to ‘0’ for ahidden channel that the virtual channel and its events may appear in EPGdisplays. This bit shall be ignored for channels which do not have thehidden bit set, so that non-hidden channels and their events may alwaysbe included in EPG displays regardless of the state of the hide_guidebit. Typical applications for hidden channels with the hide_guide bitset to ‘1’ are test signals and services accessible throughapplication-level pointers.

A service_type is a 6-bit enumerated type field that shall identify thetype of service carried in this virtual channel. Herein, FIG. 6 is anexemplary diagram of an ATSC service type according to the presentinvention and FIG. 7 is another exemplary diagram of an ATSC servicetype according to the present invention.

According to the present invention, a fixed NRT service uses aconventional ATSC terrestrial broadcasting environment. In particular, afixed NRT service, which is based on a scheme of transporting an IPdatagram via DSM-CC addressable section, can be provided by thefollowing method for example.

1. Case of transmission on virtual channel including audio and/or video:In this case, a service type of a corresponding virtual channel canfollow FIG. 6 as stipulated in the conventional ATSC specification. Inparticular, the service type follows ‘0x04’ indicating ATSC data onlyservice shown in FIG. 6. Alternatively, the service type can identify anNRT service by being included in another service type of the relatedart.

2. Case of transmission on virtual channel including NRT service only:Referring to FIG. 7, signaling can be performed to indicate an NRTapplication (‘0x08’) by allocating a new service type value.

A source_id field (16-bit) represents a programming source associatedwith a virtual channel.

A descriptors_length field is total length (in bytes) of the descriptorsfor this virtual channel that follows.

A descriptor( ) field includes zero or more descriptors, as appropriate,may be included.

An additional_descriptors_length field is total length (in bytes) of theVCT descriptor list that follows.

The trailer part is explained as follows.

CRC_(—)32 is a 32-bit field that contains the cyclic redundancy check(CRC) value that ensures a zero output from the registers in thedecoder.

NRT content is transferred through IP mechanism. In order to transfer IPdatagram through a digital broadcast stream, ATSC has regulated ATSCA/90 and A/92 specifications.

In the above description, the data service table (DST) may be receivedthrough a PID included in service_location_descriptor. And, it is ableto know a type of application and detailed information of a databroadcast stream carried on this channel through the DST.

According to FIG. 6 or FIG. 7, it is able to use a DST to identify anNRT service. The DST is explained as follows.

FIG. 8 is a diagram for a bit-stream syntax of a DST section to identityan NRT application configured according to one embodiment of the presentinvention.

The semantics of the fields comprising the data_service_table_bytesstructure are defined below.

An sdf_protocol_version field (8-bit) shall be used to specify theversion of the Service Description Framework (SDF) protocol. The valueof this field shall be set to ‘0x01’. The value ‘0x00’ and the values inthe range ‘0x02’ to ‘0xFF’ shall be ATSC reserved.

An application_count_in_section field (8-bit) shall specify the numberof applications listed in the DST section.

A compatibility_descriptor( ) field shall contain a DSM-CC compatibilitydescriptor. Its purpose shall be to signal compatibility requirements ofthe application so that the receiving platform can determine its abilityto use this data service.

An app_id_byte_length field (16-bit) shall specify the number of bytesused to identify the application. The value of this field shall accountfor the length of both the app_id_description field and the app_id_bytefields that follow. The value ‘0x0000’ shall indicate that noapp_id_description field or app_id_byte fields follow. The value‘0x0001’ is forbidden.

An app_id_description field (16-bit) shall specify the format andsemantics of the following application identification bytes.

Table 1 specifies the values and associated formats for applicationidentifier. In this case, if a value of the app_id_description field isset to ‘0x0003’, the receiver is aware that the application is an NRTapplication.

TABLE 1 Value Application Identifier Format 0x0000 DASE application0x0001 ATSC reserved 0x0002 ATSC A/92 Application 0x0003 NRT Application0x0004-0x7FFF ATSC reserved 0x8000-0xFFFF User private

An app_id_byte field (8-bit) shall represent a byte of the applicationidentifier.

A tap_count field (8-bit) shall specify the number of Tap( ) structuresused by this application.

A protocol_encapsulation field (8-bit) shall specify the type ofprotocol encapsulation used to transmit the particular data elementreferred to by the Tap( ). The following Table 2 is an exemplary diagramfor a type of the protocol encapsulation.

TABLE 2 Value Encapsulated Protocol 0x00 Not in a MPEG-2 TransportStream 0x01 Asynchronous non-flow controlled scenario of the DSM-CCDownload protocol encapsulated in DSM-CC sections 0x02 Non-streamingSynchronized Download protocol encapsulated in DSM-CC sections 0x03Asynchronous multiprotocol datagrams in Addressable Sections usingLLC/SNAP header 0x04 Asynchronous IP datagrams in Addressable Sections0x05 Synchronized streaming data encapsulated in PES 0x06 Synchronousstreaming data encapsulated in PES 0x07 Synchronized streamingmultiprotocol datagrams in PES using LLC/SNAP header 0x08 Synchronousstreaming multiprotocol datagrams in PES using LLC/SNAP header 0x09Synchronized streaming IP datagrams in PES 0x0A Synchronous streaming IPdatagrams in PES 0x0B Proprietary Data Piping 0x0C SCTE DVS 051asynchronous protocol [19] 0x0D Asynchronous carousel scenario of theDSM-CC Download protocol encapsulated in DSM-CC sections 0x0E Reservedfor harmonization with another standard body 0x0F-0x7F ATSC reserved0x80-0Xff User defined

An action_type field (7-bit) shall be used to indicate the nature of thedata referred to by the Tap( ).

A resource_location field (1-bit) shall specify the location of theAssociation Tag field matched with the association_tag value listed inthe following Tap structure. This bit shall be set to ‘0’ when thematching association_tag resides in the PMT of the current MPEG-2program. This bit shall be set to ‘1’ when the matching association_tagresides in a DSM-CC Resource Descriptor within the Network ResourcesTable of this Data Service.

A tap_id field (16-bit) shall be used by the application to identify thedata elements. The value of tap_id is scoped by the value of theapp_id_byte fields associated with the Tap( ) in the DST. The tap_idfield is unique within an application. The tap_id value is selected bythe data service provider at authoring time. It is used in theapplication as a handle to the data element.

A use field (16-bit) is used to characterize the communication channelreferenced by the association_tag. Use of use values other than ‘0x0000’is beyond the scope of this standard. The use value ‘0x0000’ indicatesthat this field is unknown.

An association_tag field (16-bit) shall uniquely identify either a dataelementary stream listed in the PMT or a DSM-CC Resource Descriptorlisted in the Network Resource Table. In the former case, the value ofthis field shall be matched with the association_tag value of anassociation_tag_descriptor in the PMT of the data service. In the lattercase, the value of this field shall match the association_tag value inthe commonDescriptorHeader structure of a DSM-CC Resource Descriptor inthe Network Resource Table of the data service.

A selector( ) field shall specify a particular data element available ina data elementary stream or a communication channel referenced by theassociation_tag field. In addition, the selector structure may indicatethe protocol required for acquiring this data element.

A tap_info_length field (16-bit) shall specify the number of bytes ofthe descriptors following the tap_info_length field.

A descriptor( ) field shall follow the descriptor format.

An app_info_length field (8-bit) shall specify the number of bytes ofthe descriptors following the app_info_length field.

Another descriptor( ) field shall follow the descriptor format.

An app_data_length field (16-bit) shall specify the length in bytes ofthe following app_data_byte fields.

An app_data_byte field (8-bit) shall represent one byte of the inputparameters and other private data fields associated with theapplication.

A service_info_length (8-bit) shall specify the number of bytes of thedescriptors following the service_info_length field.

Another descriptor( ) field shall follow the descriptor format.

A service_private_data_length field (16-bit) shall specify the length inbytes of the private fields to follow.

A service_private_data_byte field (8-bit) shall represent one byte ofthe private field.

After the NRT application has been identified, an IP stream, on which awell-known IP address for delivering NRT service signaling datadelivered via an IP layer is searched for using tap information.

If a value of protocol_encapsulation is set to ‘0x04’, an asynchronousIP datagram is transferred. If selector_type is set to ‘0x0102’, a valueof device_id, which indicates a destination address, is deliveredthrough selector_bytes. In order to accurately interpret a value of theselector_bytes, multiprotocol_encapsulation_descriptor is used. And, thenumber of valid bytes in the device_id value is signaled.

Therefore, it is able to know a multicast address (or, an address range)of an IP datagram carried on the corresponding PID via the tapinformation.

It is checked whether a well-known IP address, to which NRT servicesignaling data will be delivered, is loaded on the tap. This is receivedin the first place. An IP packet is then received.

The NRT service signaling data is extracted from the IP packet. Theextracted NRT service signaling data is delivered to and processed by anNRT application manager. An NRT service can be then initiated.

As mentioned in the above description, an NRT service signaling channelis multicasted by being encapsulated in an IP datagram via a well-knownIP address.

FIG. 9 is an exemplary diagram for a signaling method in case oftransmitting an NRT service through an ATSC broadcasting systemaccording to another embodiment of the present invention, and FIG. 10 isan exemplary flowchart for FIG. 9.

FIG. 9 shows a method of configuring a separate NRT service signalingchannel via an IP side. In this case, the NRT service signaling channelis multicasted by being encapsulated in an IP datagram via a well-knownIP address. A signaling structure for this case is shown in FIG. 9. Inparticular, it can be observed that a separate NRT service signalingchannel exists as an IP multicast stream, whereas every signaling isperformed by a PSIP side.

Referring to FIG. 10, after a power of a receiver has been turned on, ifa default channel or a channel by a user is selected [S1001], thereceiver receives a TVCT or a PMT [S1002].

Regarding this, information on a stream configuring each virtual channelis signaled to service_location_descriptor or the TVCT or ES_loop of thePMT.

Therefore, the receiver determines a type of a service provided on aselected channel by parsing service_type within the received TVCT[S1003]. For instance, if a value of the service_type is set to ‘0x02’,a type of a corresponding service provided on the selected channel maymean a digital A/V/Data service type. If a value of the service_type isset to ‘0x04’, a type of a corresponding service provided on theselected channel may mean a data only service type. If a value of theservice_type is set to ‘0x08’, a type of a corresponding serviceprovided on the selected channel may mean an NRT only service type.

As a result of the determining step S1003, if the corresponding servicetype is not a general A/V service, PID (‘0x61’) of a data service table(DST) is extracted by parsing service_location_descriptor in the channelloop of the TVCT [S1004].

Subsequently, the DST is received using the extracted PID [S1005].

It is then determined whether the corresponding service provided on theselected channel is an NRT service from the received DST [S1006]. Indoing so, the determination of a presence or absence of the NRT servicecan be performed by checking app_id_description within the DST. Forinstance, if a value of the app_id_description is set to ‘0x0003’, itmeans that the corresponding service is the NRT application.

As a result of the determining step S1006, if the corresponding serviceis the NRT service, a tap including an NRT service signaling channel isextracted [S1007]. And, stream_PID including association_tag of the tapon the PMT is extracted [S1008].

After a stream of the PID has been received, a DSM-CC addressablesection is processed [S1009].

Subsequently, after an IP packet has been received from a well-known IPaddress of the NRT service signaling channel [S1010], an NRT service isprovided by processing the NRT service signaling data within thereceived IP packet [S1011].

Regarding this, after whether the NRT application exists on the virtualchannel has been checked by the above method, an IP stream carrying thewell-known IP address, to which the NRT service signaling data carriedvia an IP layer is delivered, is searched for using tap information.

If a value of the protocol_encapsulation is set to ‘0x04’, anasynchronous IP datagram is transferred. If selector_type is set to‘0x0102’, a value of the device_id indicating a destination address isdelivered via selector_bytes.

Therefore, it is able to know a PID of a transport stream, on which thecorresponding data is carried, through the tap information on amulticast address (or, an address range) of an IP diagram. It is checkedwhether a well-known IP address, to which NRT service signaling datawill be delivered, is loaded on the tap. This is received in the firstplace. An IP packet is then received.

Subsequently, NRT service signaling data is extracted from the IPpacket. The extracted NRT service signaling data is delivered to an NRTapplication manager. A corresponding service is then initiated.

Signaling Information for the Fixed NRT Service

In the following description, NST and NCT carried on a signalinginformation channel and accompanied descriptors thereof for providinginformation for signaling an NRT service are explained in order.

As mentioned in the foregoing description of FIG. 3, an NST/NCT tablesection can be transferred by being included as an IP stream within avirtual channel.

Examples for fields carried on NST are described as follows. FIGS. 11and 12 is a diagram for a bit-stream syntax of the NST configuredaccording to one embodiment of the present invention.

In this case, although a corresponding syntax is written as an MPEG-2private section to help the understanding, a format of correspondingdata can have any type. For instance, session description protocol (SDP)is used to perform signaling via session announcement protocol (SAP).

The NST/NCT describes service information and IP access informationwithin a virtual channel carrying the NST/NCT. The NST/NCT also providesbroadcast stream information of a corresponding service using TSID thatis an identifier of a broadcast stream to which each service belongs.And, NST according to the present embodiment includes descriptioninformation of each fixed NRT service within one virtual channel. And,other side information can be included in a descriptor region.

A table_id field is an 8-bit unsigned integer number that indicates thetype of table section being defined in NST.

A section_syntax_indicator field (1-bit) shall be set to ‘0’ to alwaysindicate that this table is derived from the short form of the MPEG-2private section table.

A private_indicator field (1-bit) shall be set to ‘1’.

A section_length field (12-bit) specifies the number of remaining bytesof this table section immediately following this field. The value inthis field shall not exceed 4093 (‘0xFFD’).

A table_id_extension field (16-bit) is table-dependent. It shall beconsidered to be logically part of the table_id field providing thescope for the remaining fields. Herein, the table_id_extension fieldincludes an NST_protocol_version field. The NST_protocol_version is an8-bit unsigned integer field whose function is to allow, in the future,this NRT Service Table to carry parameters that may be structureddifferently than those defined in the current protocol. Presently, thevalue for the NST_protocol_version shall be zero. Non-zero values ofNST_protocol_version may be used by a future version of this standard toindicate structurally different tables.

A version_number field (5-bit) represents a version number of the NST.

A current_next_indicator is a one-bit indicator, which when set to ‘1’shall indicate that the NRT Service Table sent is currently applicable.When the bit is set to ‘0’, it shall indicate that the table sent is notyet applicable and will be the next table to become valid. This standardimposes no requirement that next tables (those withcurrent_next_indicator set to ‘0’) must be sent. An update to thecurrently applicable table shall be signaled by incrementing theversion_number field.

A section_number field (8-bit) shall give the section number of this NRTService table_section. The section_number of the first section in an NRTService table shall be ‘0x00’. The section_number shall be incrementedby 1 with each additional section in the NRT Service table. Alast_section_number field (8-bit) shall give the number of the lastsection (i.e., the section with the highest section_number) of the NRTService table of which this section is a part.

A carrier_frequency field (32-bit) indicates transport frequencycorresponding to a channel.

A channel_TSID field (16-bit) represents a transport stream including anMPEG-2 program referenced to a virtual channel and an MPEG-2 TSIDassociated with the transport stream.

A source_id field (16-bit) represents a programming source associatedwith a virtual channel.

A num_NRT_services field (8-bit) specifies the number of NRT services inthis NST section.

According to one embodiment of the present invention, the NST providesinformation for a plurality of fixed NRT services using a ‘for’ loop.Field information which is included in each fixed NRT service isexplained as follows.

An NRT_service_status is a 2-bit enumerated field that shall identifythe status of this NRT Service. The most significant bit shall indicatewhether this NRT Service is active (when set to ‘1’) or inactive (whenset to ‘0’) and the least significant bit shall indicate whether thisNRT Service is hidden (when set to ‘1’) or not (when set to ‘0’). Hiddenservices are normally used for proprietary applications, and ordinaryreceiving devices should ignore them.

A SP_indicator is a 1-bit field that shall indicate, when set, thatservice protection is applied to at least one of the components neededto provide a meaningful presentation of this NRT Service.

A CP_indicator is a 1-bit field that shall indicate, when set, thatcontent protection is applied to at least one of the components neededto provide a meaningful presentation of this NRT Service.

An NRT_service_id is a 16-bit unsigned integer number that shalluniquely identify this NRT Service within the scope of this NRTBroadcast. The NRT_service_id of a service shall not change throughoutthe life of the service. To avoid confusion, it is recommended that if aservice is terminated, then the NRT_service_id for the service shouldnot be used for another service until after a suitable interval of timehas elapsed.

A short_NRT_service_name_length is a three-bit unsigned integer thatshall indicate the number of byte pairs in the short_NRT_service_namefield. This value is shown as m in the No. of Bits column for theshort_NRT_service_name field. When there is no short name of this NRTservice, the value of this field shall be ‘0’.

A short_NRT_ service_name field is a short name of the NRT Service. Whenthere is no short name of this NRT Service, this field shall be filledwith NULLs (‘0x00’).

An NRT_service_category is a 6-bit enumerated type field that shallidentify the type of service carried in this IP Service.

A num_components field (5-bit) specifies the number of IP streamcomponents in this NRT Service.

An IP_version_flag is a 1-bit indicator, which when set to ‘0’ shallindicate that source_IP_address, NRT_service_destination_IP_address, andcomponent_destination_IP_address fields are IPv4 addresses. The value of1 for this field is reserved for possible future indication thatsource_IP_address, NRT_service_destination_IP_address, andcomponent_destination_IP_address fields are for IPv6.

A source_IP_address_flag is a 1-bit Boolean flag that shall indicate,when set, that a source IP address value for this NRT Service is presentto indicate a source specific multicast.

An NRT_service_destination_IP_address_flag is a 1-bit Boolean flag thatindicates, when set to ‘1’, that an NRT_service_destination_IP_addressvalue is present, to serve as the default IP address for the componentsof this NRT Service).

A source_IP_address field shall be present if the source_IP_address_flagis set to ‘1’ and shall not be present if the source_IP_address_flag isset to ‘0’. If present, this field shall contain the source IP addressof all the IP datagrams carrying the components of this NRT Service. Theconditional use of the 128 bit-long address version of this field is tofacilitate possible use of IPv6 in the future, although use of IPv6 isnot currently defined.

An NRT_service_destination_IP_ address field shall be present if theNRT_service_destination_IP_address_flag is set to ‘1’ and shall not bepresent if the NRT_service_destination_IP_address_flag is set to ‘0’. Ifthis NRT_service_destination_IP_address is not present, then thecomponent_destination_IP_address field shall be present for eachcomponent in the num_components loop. The conditional use of the 128bit-long address version of this field is to facilitate possible use ofIPv6 in the future, although use of IPv6 is not currently defined.

According to one embodiment of the present invention, the NST providesinformation for a plurality of components using ‘for’ loop.

An essential_component_indicator is a one-bit indicator which, when setto ‘1’, shall indicate that this component is an essential component forthe NRT Service. Otherwise, this field indicates that this component isan optional component.

A port_num_count field shall indicate the number of destination UDPports associated with this UDP/IP stream component. The values of thedestination UDP port numbers shall start from thecomponent_destination_UDP_port_num field and shall be incremented byone.

A component_destination_IP_address_flag is a 1-bit Boolean flag thatshall indicate, when set to ‘1’, that the component_destination_IP_address is present for this component.

A component_destination_IP_address field shall be present if thecomponent_destination_IP_address_flag is set to ‘1’ and shall not bepresent if the component_destination_IP_address_flag is set to ‘0’. Whenthis field is present, the destination address of the IP datagramscarrying this component of the NRT Service shall match the address inthis field. When this field is not present, the destination address ofthe IP datagrams carrying this component shall match the address in theNRT_service_destination_IP_address field. The conditional use of the 128bit-long address version of this field is to facilitate possible use ofIPv6 in the future, although use of IPv6 is not currently defined.

A component_destination_UDP_port_num is a 16-bit unsigned integer fieldthat represents the destination UDP port number for this UDP/IP streamcomponent.

A num_component_level_descriptors is a 16-bit unsigned integer field,that represents the number of descriptors providing additionalinformation for IP stream component, may be included.

A component_level_descriptors field includes one or more descriptorsproviding additional information for this IP stream component, may beincluded.

A num_NRT_service_level_descriptors field (4 bit) specifies the numberof NRT service level descriptors for this service.

An NRT_service_level_descriptor( ) field includes zero or moredescriptors providing additional information for this NRT Service, maybe included. This detailed service type can include a portal service forproviding web contents, Push VOD, A/V download or the like.

A num_virtual_channel_level_descriptors field (4-bit) specifies thenumber of virtual channel level descriptors for this virtual channel.

A virtual_channel_level_descriptor( ) includes zero or more descriptorsproviding additional information for the virtual channel which this NSTdescribes, may be included.

An NRT service is transferred via FLUTE and access information in an NSTtable is connected to FLUTE session information as follows. ASource_IP_address becomes a source IP address of a same server thattransmits all channels of FLUTE session.NRT_service_destination_IP_Address is signaled if there exists adestination IP address at a session level of this FLUTE session.

A component can be mapped to a channel within a FLUTE session and cansignal a separate destination IP address per channel (this is differentfrom an IP address signaled by a session unit) throughcomponent_destination_IP_address. Moreover, a destination port number issignaled through component_destination_UDP_port_num. And, it is able toadditionally designate the number of destination ports starting fromcomponent_destination_UDP_port_num through port_num_count.

By designating ports to a plural number, it is able to construct aplurality of channels for one destination IP address. In this case, onecomponent is able to designate a plurality of channels. Yet, it ispreferable that a channel is identified via a destination IP address ingeneral. In this case, one channel can be regarded as mapped to onecomponent.

An NRT_component_descriptor( )

Content items/files for an NRT service are transferred through FLUTE andcorresponding FLUTE session information is signaled using accessinformation in an NST table.

FIG. 13 is an exemplary diagram for a bit-stream syntax ofNRT_component_descriptor( ) configured according to one embodiment ofthe present invention.

An NRT_component_descriptor( ) shall appear in the component descriptorloop of each component of each NRT Service in the NST and all parametersin the descriptor shall correspond to the parameters in use for thatcomponent of the NRT Service.

In the following description, each field carried on NRT_component_descriptor shown in FIG. 13 is described.

A descriptor_tag is 8-bit unsigned integer. It shall have the value,identifying this descriptor as the NRT_ component_descriptor.

A descriptor_length is 8-bit unsigned integer shall specify the length(in bytes) immediately following this field up to the end of thisdescriptor.

A component_type field (7-bit) shall identify the encoding format of thecomponent. The value may be any of the values assigned by IANA for thepayload_type of an RTP/AVP stream [10], or it may be any of the valuesin Table 3 assigned by this document, or it may be a “dynamic value”within the range of 96 to 127. For components consisting of mediacarried via RTP, the value of this field shall match the value in thepayload_type field in the RTP header of the IP stream carrying thiscomponent.

Note that additional values of the component_type field within the rangeof 43 to 71 can be defined in future versions of this standard. The NRTservice stream transmitted through FLUTE protocol further requiresparameters to signal a FLUTE session as a Table 3. In the Table 3, ‘38’of component_type being defined for FLUTE component in the ATSC or ‘43’of component_type newly being defined for transmission NRT may be used.

TABLE 3 component_type Meaning  0-34 Assigned or reserved by IANA,except that 20-24, 27, and 29-30 are unassigned 35 H. 264/AVC videostream component (assigned by ATSC use) 36 SVC enhancement layer streamcomponent (assigned by ATSC use) 37 HE AAC v2 audio stream component(assigned by ATSC use) 38 FLUTE file delivery session (assigned by ATSCuse) 39 STKM stream component (assigned by ATSC use) 40 LTKM streamcomponent (assigned by ATSC use) 41 OMA-RME DIMS stream component(assigned by ATSC use) 42 NTP timebase stream component (assigned byATSC use) 43-71 [Unassigned by IANA andreserved by ATSC use] 72-76Reserved by IANA 77-95 Unassigned by IANA  96-127 Designated by IANA fordynamic use

A num_STKM_streams is an 8-bit unsigned integer field that shallidentify the number of STKM streams associated with this component.

A STKM_stream_id is an 8-bit unsigned integer field that shall identifyan STKM stream where keys to decrypt this protected component can beobtained, by reference to the STKM_stream_id in the component descriptorfor the STKM stream.

An NRT_component_data (component_type) is explained as follow. TheNRT_component_data( ) element provides the encoding parameters and/orother parameters necessary for rendering this component. The structureof the NRT_component_data is determined by the value of component_typefield.

An NRT content or file is transmitted using a FLUTE session descriptortransferred through the NRT_component_descriptor( ).

The FDT of the FLUTE sessions which is used to deliver the items listsall the content items and gives their sizes, data types, and otherinformation relevant to the acquisition of the items.

Therefore, the present invention obtains information for accessing aFLUTE session carrying a corresponding content using NST to receive acontent selected from a service guide constructed using NCT. And, thepresent invention intends to map information on a content item of NCT toinformation on a file transferred via a corresponding FLUTE session. Inthis case, identification of a service including the selected contentitem can be done via the NRT_service_id of the aforesaid NST. Yet, asmentioned in the foregoing description of FIG. 3, in order to know oneor more content items included in each NRT service and files belongingto the content items in further detail, mapping to a content identifierwithin FDT information on a FLUTE session is necessary rather thaninformation on the FLUTE session carrying the corresponding contentitem(s).

The NRT service is transferred via FLUTE and access information in anNST is connected to FLUTE session information as follows.

A Source_IP_address becomes a source IP address of a same server thattransmits all channels of FLUTE session. NRT_ service_ destination_ IP_Address is signaled if there exists a destination IP address at asession level of this FLUTE session.

A component can be mapped to a channel within a FLUTE session and cansignal a separate destination IP address per channel (this is differentfrom an IP address signaled by a session unit) throughcomponent_destination_IP_address. Moreover, a destination port number issignaled through component_destination_UDP_port_num. And, it is able toadditionally designate the number of destination ports starting fromcomponent_destination_UDP_port_num through port_num_count.

By designating ports to plural number, it is able to construct aplurality of channels for one destination IP address. In this case, onecomponent is able to designate a plurality of channels. Yet, it isrecommended that a channel is identified via a destination IP address ingeneral. In this case, one channel can be regarded as mapped to onecomponent.

In order to signal an additional attribute of a component constructing asession, it is able to use component_attribute_byte. Additionalparameters required for signaling a FLUTE session can be signaledthrough this field.

In order to signal the FLUTE session, parameters are necessary. Suchparameters include necessary parameters and parameters which areselectively necessary in association with the FLUTE session. First, thenecessary parameters include a “source IP address” parameter, a “numberof channels in the session” parameter, a “destination IP address andport number for each channel in the session” parameter, a “TransportSession Identifier (TSI) of the session” parameter and a “start time andend time of the session” parameter, and the parameters which areselectively necessary in association with the FLUTE session include an“FEC object transmission information” parameter, a “some informationthat tells a receiver in the first place, that the session containsfiles that are of interest”, and a “bandwidth specification” parameter.

The “number of channels in the session” parameter may be explicitlyprovided or may be obtained by summing the number of streams configuringthe session. Among the parameters, the “start time and end time of thesession” parameter may be signaled through the SMT suggested by thepresent invention, and the “source IP address” parameter, the“destination IP address and port number for each channel in the session”parameter, the “Transport Session Identifier (TSI) of the session”parameter and the “number of channels in the session” parameter may besignaled through session_description_descriptor.

An NRT_component_data_descriptor

FIG. 14 is an exemplary diagram for a bit-stream syntax of an NCTsection configured according to one embodiment of the present invention.

A single NRT service may contain multiple FLUTE sessions. Each sessionmay be signaled using one or more FLUTE component descriptors, dependingon the IP addresses and ports used for the sessions.

In the following description, each field ofNRT_component_data_descriptor is explained in detail.

A TSI is a 16-bit unsigned integer field, which shall be the TransportSession Identifier (TSI) of the FLUTE session.

A session_start_time indicates the time at which the FLUTE sessionstarts. If the value of this field is set to all zero, then it shall beinterpreted to indicate that the session has already started.

A session_end_time indicates the time at which the FLUTE session ends.If the value of this field is set to all zero, then it shall beinterpreted to mean that the session continues indefinitely.

A tias_bandwidth_indicator is a 1-bit field that flags the inclusion ofTransport Independent Application Specific (TIAS) bandwidth information.This bit shall be set to ‘1’ to indicate the TIAS bandwidth field ispresent, and it shall be set to ‘0’ to indicate the TIAS bandwidth fieldis absent.

An as_bandwidth_indicator is a 1-bit field that flags the inclusion ofApplication Specific (AS) bandwidth information. This bit shall be setto ‘1’ to indicate the AS bandwidth field is present, and it shall beset to ‘0’ to indicate the AS bandwidth field is absent.

A FEC_OTI_indicator is a 1-bit indicator that indicates whether FECObject Transmission Information is provided.

A tias_bandwidth field has a value. This value shall be oneone-thousandth of the TIAS maximum bandwidth, rounded up to the nexthighest integer if necessary.

An as_bandwidth has a value. This value shall be the AS maximumbandwidth.

A FEC_encoding_id field identifies a FEC encoding ID used in this FLUTEsession.

A FEC_instance_id field identifies a FEC instance ID used in this FLUTEsession.

By signaling the above described parameters via FLUTE component databytes, it is able to provide all information mandatory to receive aFLUTE session. And, it is ale to use a method of receiving FDT via thissession, obtaining information all files carried on a FLUTE session viathe received FDT and receiving these files.

This FLUTE component descriptor can be delivered viacomponent_level_descriptor loop of NST. In case that there is aplurality of FLUTE channels, such parameters at a session level as TSI,session_start_time, session_end_time and the like should be signaledonly once. Hence, one of the components of several channels can transmita FLUTE component descriptor via Component_level_descriptor loop.

In the following description, NCT is explained. FIG. 15 is a diagram fora bit-stream syntax of an NCT section configured according to oneembodiment of the present invention.

In the following description, explained is NCT associated withsignaling/announcement of an NRT content transmitted per NRT contentdelivery channel signaled via the above described NST.

In FIG. 15, an NCT is newly defined to signal NRT content. This is justone of various embodiments and other methods are considerable as well.Via NCT, it is able to signal an NRT content carried on a specific NRTcontent delivery channel. Information of each field constructing an NCTsection is explained in detail as follows.

First of all, a table_id field (8 bits) identifies whether acorresponding table section is a table section constructing an NCT.

An NRT_service_id field describes a service_id of an NRT contentdelivery channel that delivers a content described in NCT.

A version_number field indicates a version_number of NCT. Hence, areceiver is able to know whether an NCT content is changed, using theversion_number.

A num_contents_in_section field indicates the number of contentsdescribed in NCT or the number of contents (or, files) carried on avirtual channel described as source_id.

A content_version field indicates a version number for content (or afile) having a specific content_id value. In particular, if acontent_id, which was received and stored in advance by a receiver, isset to ‘0x0010’, a same content, i.e., a file having a content_id valueset to ‘0x0010’ is transferred. If the content_version is different tothat of the previously received and stored content, a content newlyannounced via NCT is received to update or replace the previously storedcontent. According to the present embodiment, the content_version fieldmeans a serial number indicating a version of release but may be able torepresent a real published (released) time in direct. In this case, ifit is difficult to represent a published time using the content_versionfield, it is able to use a new field capable of representing thepublished (released) time.

A content_id field indicates an ID value capable of identifying content(or, a file), which will be received and stored, uniquely.

A content_available_ start_ time field indicates a start time of a FLUTEsession capable of receiving content. And, a content_available_end_timefield indicates an end time of the FLUTE session capable of receivingthe content.

A content_length_in_seconds field indicates a real playback time of acorresponding content by a unit of second if the content (or file) is anA/V file.

A content_size field indicates a size of content (or, a file) by a byteunit.

A content_delivery_bit_rate field indicates a bit rate for transmittingcontent (or, a file) and means a target bit rate. In particular, thisfield indicates a bandwidth that will be allocated when a serviceprovider or a broadcasting station transmits a corresponding content.Using this information, a receiver is aware of a minimum time consumedfor receiving a corresponding file using the content_size and thecontent_delivery_bit_rate. Namely, it is able to provide a user withcorresponding information by estimating a time taken to receive content.In this case, minimum time for receiving is obtained from calculating(content_size*8)/(content_delivery_bit_rate) by a unit of seconds.

A content_title_length field indicates a length of content_title_text( )by a byte unit. Using this, it is able to know how many bytes need to beread to enable a receiver to exactly obtain content_title_text( )information.

A content_title_text( ) field is a content title in the format of amultiple string structure (MSS).

As a method of constructing the above described NST, one or more NRTchannels can include one channel.

In this disclosure, an NRT channel is constructed by an NRT serviceunit. And, it is capable to have at least one FLUTE session fortransferring a file via FLUTE.

In general, a FLUTE session can be uniquely identified/referenced usingsuch a parameter as a TSI, an IP, a port address and the like and istemporally bound to a session_start_time and a session_end_time.

In constructing a table, using session_start_time and session_end_time,a FLUTE session during this time period is announced.

It is able to configure information on all NRT channels, which arecurrently transmitted or shall be transmitted in the future, with onetable. This can be divided into a present time (a predetermined periodfrom a present time) and a future time (after the period defined as thepresent time). Alternatively, the information can be sent by beingdivided into three sections including a predetermined time within apresent time (e.g., 24 hours), a predetermined time after the formerpredetermined time (e.g., 24 hours) and a time after the latterpredetermined time and then constructing tables for the three sections,respectively.

Moreover, using a table_id, it is able to discriminate whether itindicates guide information on a currently receivable content or guideinformation on a content receivable in the future. This relates to amethod of separating an NRT service receivable within a short time rangefrom a current time and services receivable after the time intodifferent tables and then transmitting the tables.

In case of receiving the guide information on a content receivable inthe future, a receiver performs temporal alignment usingavailable_start_time and available_end_time information of each contentand enables the guide information on the NRT service to be outputted toa user.

Yet, despite changing a table constructing method different from theabove described example, each field constructing a table element shallbe identical.

An NRT Service Signaling Architecture

FIG. 16 is a diagram for an NRT service signaling structure configuredaccording to another embodiment of the present invention.

Referring to FIG. 16, each ATSC virtual channel includes at least one ofcontent delivery channel to be transferred as IP stream including eachNRT service and NRT service signaling channel to be transferred as IPstream transferring signaling information of each content deliverychannel. At this time, the NST is transferred via the NRT servicesignaling channel. The NST includes a table entry and signals thecontent delivery channel transferring corresponding NRT service. Forinstance, three NRT channels are provided on ATSC Virtual Channel 0 andNRT channels 0, 1 and 2 are NRT content delivery channels. In case ofATSC Virtual Channel 1, three NRT channels are provided on NRT channel5. And, NRT channels 3, 4 and 5 are NRT content delivery channels. Inparticular, one virtual channel includes one or more NRT channels andthe NRT channel can be an NRT content delivery channel. And, an NST isable to identify each of the NRT channels or each of the NRT contentdelivery channels. Each of the NRT channels carries an IP stream. Onthis NRT service signaling, a signaling flow according to a method ofaccessing an NRT content delivery channel is available.

A Fixed NRT Content Delivery Channel

As a method of accessing an NRT content delivery channel for carryingNRT content, the following method is available.

A method of directly signaling NRT content delivery channel informationvia an NST table is for directly delivering basic information on an NRTchannel and access information via an NST. If an NST side performs thisNRT channel metadata transmission, the following advantages exist.

First of all, in this case, by directly signaling in NST without anadditional process for receiving and processing separate service guideinformation, it is able to receive channel metadata in the early timingpoint. Therefore, it is able to raise a service access speed. Moreover,it is able to perform update signaling for a changed item of a channelin a broadcasting environment more quickly and by real time.

Thus, if NRT service information carrying an NRT content deliverychannel on an NST is directly signaled, a content delivery channelaccess is possible with an NST only without a separate signalingprocess.

An NRT content delivery channel for carrying real NRT content can havean NRT channel type value set to ‘0x0F’.

An NRT Content Delivery Channel Details Descriptor

In order to perform signaling on an NRT content delivery channel via anNST in the course of the above process, the following method isavailable. It is able to identify an NRT service carrying an NRT contentdelivery channel if a service category value is set to ‘0x0F’.Additional information of an NRT content delivery channel can bedelivered being transmitted in a manner that an NRT content deliverychannel details descriptor exemplarily shown in FIG. 17 is inserted in adescriptor loop of NST.

FIG. 17 is a diagram for a bit-stream syntax of an NRT Content deliverychannel details descriptor configured according to one embodiment of thepresent invention.

Fields of an NRT Content delivery channel details descriptor areexplained in detail as follows.

A descriptor_tag is 8-bit unsigned integer that has the value ‘0xTBD’,identifying this descriptor asNRT_content_delivery_channel_details_descriptor.

A descriptor_length is 8-bit unsigned integer that specifies the length(in bytes) immediately following this field up to the end of thisdescriptor.

A storage_reservation is 32-bit unsigned integer that specifies minimumdevice storage (in bytes) required for subscription to this channel.

An Updated is 32-bit unsigned integer, which shall represent time whenthe channel metadata was last updated as the number of GPS seconds since00:00:00 UTC, Jan. 6, 1980.

A content_types_length field shall specify the length (in bytes) of thecontent_types_text ( ).

A content_types_text( ) field shall give a comma-separated list ofstrings that describe the type of channel content e.g. by “category”,“tag” or “relation”.

A mime_types_length field shall specify the length (in bytes) of themime_types_text( ).

A mime_types_text( ) field shall give a comma-separated list of MIMEtypes for content items in the offered channel.

A charging_rules_length field shall specify the length (in bytes) of thecharging_rules_text( ).

A charging_rules_text( ) field shall give Information that at leastdefines who is responsible for the channel charging, charging method(based upon a subscription or a consumption).

A num_purchase_options field (8-bit) shall specify the number ofpurchase options in this NRT Content delivery channel descriptor.

A purchase_option_id_length field shall specify the length (in bytes) ofthe purchase_option_id_text ( ).

A purchase_option_id_text( ) field shall give an identifier of thepurchase option, that will be used to identify the selected option.

A cost_information_flag is a 1-bit Boolean flag that shall indicate,when set to ‘1’, that the cost_information is present for thiscomponent.

A price_information_flag is a 1-bit Boolean flag that shall indicate,when set to ‘1’, that the amount and currency is present for thiscomponent.

A cost_information_length field shall specify the length (in bytes) ofthe cost_information_text( ).

A cost_information_text ( ) field shall give an identifier of thepurchase option, that will be used to identify the selected option.

An amount is a 32-bit float, which shall specify the monetary value ofthe price for this purchase option.

A currency is a 16-bit unsigned integer, which shall specify themonetary currency codes.

The above described descriptor is included in a position ofservice_level_descriptor within NST or can be included in a position ofcontent_level_descriptor within NCT.

A Protocol for a Mobil NRT Service

Hereinafter, the mobile NRT service is specified as follows.

FIG. 18 is a diagram for a protocol stack of a mobile NRT serviceconfigured according to one embodiment of the present invention.

In FIG. 18, an IP datagram containing signaling information may betransmitted without using an MPEG-2 TS format, by inserting an adaptionlayer between an IP layer and a physical layer.

In FIG. 18, an NRT service for a mobile service is packetized accordingto a User Datagram Protocol (UDP) scheme in the IP layer, and a UDPpacket is packetized again according to an IP scheme, thereby obtainingUDP/IP packet data. In the present specification, the packetized UDP/IPpacket data is referred to as an IP datagram for simplicity. Inaddition, a signaling information channel containing an SMT is alsopacketized according to a UDP scheme and a UDP packet is packetizedagain according to an IP scheme, thereby obtaining UDP/IP packet data.

In FIG. 18, an OMA BCAST SG and NRT content items/files are transmittedaccording to a FLUTE scheme and are packetized again according to anAsynchronous Layered Coding/Layered Coding Transport (ALC/LCT) scheme.An ALC/LCT packet is packetized again according to an IP scheme, therebyobtaining ALC/LCT/UDP/IP packet data.

Moreover, an RS frame including the packetized IP datagram is generated.The generated RS frame is transmitted to a receiving system modulated bypre-defined transmission method (e.g. VSB).

A Receiving System for Processing a Mobile NRT Service

FIG. 19 is an exemplary block diagram of a receiving system according toone embodiment of the present invention.

Referring to FIG. 19, the receiving system according to the presentinvention may include an operation controller 100, a tuner 111, ademodulator 112, an equalizer 113, a known sequence detector (or knowndata detector) 114, a block decoder 115, a primary Reed-Solomon (RS)frame decoder 116, a secondary RS frame decoder 117, a signaling decoder118, and a baseband controller 119. The receiving system according tothe present invention may further include an FIC handler 121, a servicemanager 122, a service signaling handler 123, and a first storage unit124. The receiving system according to the present invention may furtherinclude a primary RS frame buffer 131, a secondary RS frame buffer 132,and a transport packet (TS) handler 133. The receiving system accordingto the present invention may further include an Internet Protocol (IP)datagram handler 141, a descrambler 142, an User Datagram Protocol (UDP)datagram handler 143, a Real-time Transport Protocol/Real-time TransportControl Protocol (RTP/RTCP) datagram handler 144, a Network TimeProtocol (NTP) datagram handler 145, a service protection stream handler146, a second storage unit 147, an Asynchronous Layered Coding/LayeredCoding Transport (ALC/LCT) stream handler 148, a decompressor 149, anExtensible Mark-up Language (XML) parser 150, and a Field Device Tool(FDT) handler 151. The receiving system according to the presentinvention may further include an Audio/Video (A/V) decoder 161, a filedecoder 162, a third storage unit 163, a middle ware (M/W) engine 164,and a Service Guide (SG) handler 165. The receiving system according tothe present invention may further include an Electronic Program Guide(EPG) manager 171, an application manager 172, and a User Interface (UI)manager 173.

Herein, for simplicity of the description of the present invention, theoperation controller 100, the tuner 111, the demodulator 112, theequalizer 113, the known sequence detector (or known data detector) 114,the block decoder 115, the primary RS frame decoder 116, the secondaryRS frame decoder 117, the signaling decoder 118, and the basebandcontroller 119 will be collectively referred to as a baseband processor110. The FIC handler 121, the service manager 122, the service signalinghandler 123, and the first storage unit 124 will be collectivelyreferred to as a service multiplexer 120. The primary RS frame buffer131, the secondary RS frame buffer 132, and the TS handler 133 will becollectively referred to as an IP adaptation module 130. The IP datagramhandler 141, the descrambler 142, the UDP datagram handler 143, theRTP/RTCP datagram handler 144, the NTP datagram handler 145, the serviceprotection stream handler 146, the second storage unit 147, the ALC/LCTstream handler 148, the XML parser 150, and the FDT handler 151 will becollectively referred to as a common IP module 140. The A/V decoder 161,the file decoder 162, the third storage unit 163, the M/W engine 164,and the SG handler 165 will be collectively referred to as anapplication module 160.

In addition, although the terms used in FIG. 19 are selected fromgenerally known and used terms, some of the terms mentioned in thedescription of FIG. 19 have been selected by the applicant at his or herdiscretion, the detailed meanings of which are described in relevantparts of the description herein. Furthermore, it is required that thepresent invention is understood, not simply by the actual terms used butby the meaning of each term lying within.

Referring to FIG. 19, the operation controller 100 controls theoperation of each block included in the baseband processor 110.

By tuning the receiving system to a specific physical channel frequency(or physical transmission channel frequency, PTC), the tuner 111 enablesthe receiving system to receive main service data, which correspond tobroadcast signals for fixed-type broadcast receiving systems, and mobileservice data, which correspond to broadcast signals for mobile broadcastreceiving systems. At this point, the tuned frequency of the specificphysical channel is down-converted to an intermediate frequency (IF)signal, thereby being outputted to the demodulator 112 and the knownsequence detector 114. The passband digital IF signal being outputtedfrom the tuner 111 may only include main service data, or only includemobile service data, or include both main service data and mobileservice data.

The demodulator 112 performs self-gain control, carrier recovery, andtiming recovery processes on the passband digital IF signal inputtedfrom the tuner 111, thereby modifying the IF signal to a basebandsignal. Then, the demodulator 112 outputs the baseband signal to theequalizer 113 and the known sequence detector 114. The demodulator 112uses the known data symbol sequence inputted from the known sequencedetector 114 during the timing and/or carrier recovery, therebyenhancing the demodulating performance.

The equalizer 113 compensates channel-associated distortion included inthe signal demodulated by the demodulator 112. Then, the equalizer 113outputs the distortion-compensated signal to the block decoder 115. Byusing a known data symbol sequence inputted from the known sequencedetector 114, the equalizer 113 may enhance the equalizing performance.Furthermore, the equalizer 113 may receive feed-back on the decodingresult from the block decoder 115, thereby enhancing the equalizingperformance.

The known sequence detector 114 detects known data place (or position)inserted by the transmitting system from the input/output data (i.e.,data prior to being demodulated or data being processed with partialdemodulation). Then, the known sequence detector 114 outputs thedetected known data position information and known data sequencegenerated from the detected position information to the demodulator 112,the equalizer 113, and the baseband controller 119. Additionally, inorder to allow the block decoder 115 identifying the mobile service datathat have been processed with additional encoding by the transmittingsystem and the main service data that have not been processed with anyadditional encoding, the known sequence detector 114 outputs suchcorresponding information to the block decoder 115.

If the data channel-equalized by the equalizer 113 and inputted to theblock decoder 115 correspond to data processed with both block-encodingof serial concatenated convolution code (SCCC) method andtrellis-encoding by the transmitting system (i.e., data within the RSframe, signaling data), the block decoder 115 may performtrellis-decoding and block-decoding as inverse processes of thetransmitting system. On the other hand, if the data channel-equalized bythe equalizer 113 and inputted to the block decoder 115 correspond todata processed only with trellis-encoding and not block-encoding by thetransmitting system (i.e., main service data), the block decoder 115 mayperform only trellis-decoding.

The signaling decoder 118 decodes signaling data that have beenchannel-equalized and inputted from the equalizer 113. It is assumedthat the signaling data (or signaling information) inputted to thesignaling decoder 118 correspond to data processed with bothblock-encoding and trellis-encoding by the transmitting system. Examplesof such signaling data may include transmission parameter channel (TPC)data and fast information channel (FIC) data. For example, among thedata that are being inputted, the signaling decoder 118 performsregressive turbo decoding of a parallel concatenated convolution code(PCCC) method on data corresponding to the signaling information region.Subsequently, the signaling decoder 118 separates FIC data and TPC datafrom the regressive-turbo-decoded signaling data. Additionally, thesignaling decoder 118 performs RS-decoding as inverse processes of thetransmitting system on the separated TPC data, thereby outputting theprocessed data to the baseband controller 119. Also, the signalingdecoder 118 performs deinterleaving in sub-frame units on the separatedFIC data, so as to perform RS-decoding as inverse processes of thetransmitting system on the deinterleaved FIC data, thereby outputtingthe processed data to the FIC handler 121. The FIC data beingdeinterleaved and RS-decoded from the signaling decoder 118 andoutputted to the FIC handler 121 are transmitted in units of FICsegments.

The FIC handler 121 receives FIC data from the signaling decoder 118, soas to extract signaling information for service acquisition (i.e.,mapping information between an ensemble and a mobile service). In orderto do so, the FIC handler 121 may include an FIC segment buffer, an FICsegment parser, and an FIC chunk parser.

The FIC segment buffer buffers FIC segment groups being inputted in M/Hframe units from the signaling decoder 118, thereby outputting thebuffered FIC segment groups to the FIC segment parser. Thereafter, theFIC segment parser extracts the header of each FIC segment stored in theFIC segment buffer so as to analyze the extracted headers. Then, basedupon the analyzed result, the FIC segment parser outputs the payload ofthe respective FIC segments to the FIC chunk parser. The FIC chunkparser uses the analyzed result outputted from the FIC segment parser soas to recover the FIC chunk data structure from the FIC segmentpayloads, thereby analyzing the received FIC chunk data structure.Subsequently, the FIC chunk parser extracts the signaling informationfor service acquisition. The signaling information acquired from the FICchunk parser is outputted to the service manager 122.

Meanwhile, the service signaling handler 123 consists of a servicesignaling buffer and a service signaling parser. Herein, the servicesignaling handler 123 buffers table sections of a service signalingchannel being transmitted from the UDP datagram handler 143, therebyanalyzing and processing the buffered table sections. Similarly, thesignaling information processed by the service signaling handler 123 isalso outputted to the service manager 122.

The service signaling channel transferring a service map table (SMT)section is received via the RS frame according to one embodiment of thepresent invention. The RS frame is a type of UDP/IP packet having awell-known IP destination address and well-known destination UDP portnumber. Accordingly, a receiver can process the SMT section and thereinthe descriptor without separate information.

In this case, the SMT section provides signaling information related toall services in the Ensemble including the corresponding SMT section.Accordingly, the receiver can access an IP stream component in wantedservice using the SMT section data and provide corresponding service touser.

The SMT section data is stored the first storage unit 124 collected bythe service manager 122. In this case, the stored SMT section data ischanged a service map format by the service manager 122.

The service manager 122 uses the signaling information collected fromeach of the FIC handler 121 and the service signaling handler 123, so asto configure a service map. Thereafter, the service manager 122 uses aservice guide (SG) collected from the service guide (SG) handler 165 soas to draw up a program guide. Then, the service manager 122 controlsthe baseband controller 119 so that a user can receive (or be providedwith) a user-requested mobile service by referring to the service mapand service guide. Furthermore, the service manager 122 may also controlthe receiving system so that the program guide can be displayed on atleast a portion of the display screen based upon the user's input.

The first storage unit 124 stores the service map and service guidedrawn up by the service manager 122. Also, based upon the requests fromthe service manager 122 and the EPG manager 171, the first storage unit124 extracts the required data, which are then transferred to theservice manager 122 and/or the EPG manager 171.

The operation controller 100 stores a service map and a service guideprovided by the service manager 122. Moreover, the operation controller100 extracts required data according to a request of the service manager122 or the EPG manager 171 and transfers the extracted data to theservice manager 122 or the EPG manager 171.

The operation controller 100 receives the known data place informationand TPC data, thereby transferring M/H frame time information,information indicating whether or not a data group exists in a selectedparade, place information of known data within a corresponding datagroup, power control information, and so on to each block within thebaseband processor 110. The TPC data will be described in detail in alater process.

Meanwhile, according to the present invention, the transmitting systemuses RS frames by encoding units. Herein, the RS frame may be dividedinto a primary RS frame and a secondary RS frame. However, according tothe embodiment of the present invention, the primary RS frame and thesecondary RS frame will be divided based upon the level of importance ofthe corresponding data.

The primary RS frame decoder 116 receives the data outputted from theblock decoder 115. At this point, according to the embodiment of thepresent invention, the primary RS frame decoder 116 receives only themobile service data that have been Reed-Solomon (RS)-encoded and/orcyclic redundancy check (CRC)-encoded from the block decoder 115.

Herein, the primary RS frame decoder 116 receives at least one of themobile service data, the NRT service data, the SMT section data, OMABCAST SG data, and not the main service data. The primary RS framedecoder 116 performs inverse processes of an RS frame encoder (notshown) included in the digital broadcast transmitting system, therebycorrecting errors existing within the primary RS frame. Morespecifically, the primary RS frame decoder 116 forms a primary RS frameby grouping a plurality of data groups and, then, corrects errors inprimary RS frame units. In other words, the primary RS frame decoder 116decodes primary RS frames, which are being transmitted for actualbroadcast services. The primary RS frame decoded by the primary RS framedecoder 116 outputs to the primary RS frame buffer 131. The primary RSframe buffer 131 buffers the primary RS frame, and then configures anM/H TP in each row unit. The M/H TPs of the primary RS frame outputs tothe TP handler 133.

Additionally, the secondary RS frame decoder 117 receives the dataoutputted from the block decoder 115. At this point, according to theembodiment of the present invention, the secondary RS frame decoder 117receives only the mobile service data that have been RS-encoded and/orCRC-encoded from the block decoder 115. Herein, the secondary RS framedecoder 117 receives only the mobile service data and not the mainservice data. The secondary RS frame decoder 117 performs inverseprocesses of an RS frame encoder (not shown) included in the digitalbroadcast transmitting system, thereby correcting errors existing withinthe secondary RS frame. More specifically, the secondary RS framedecoder 117 forms a secondary RS frame by grouping a plurality of datagroups and, then, corrects errors in secondary RS frame units. In otherwords, the secondary RS frame decoder 117 decodes secondary RS frames,which are being transmitted for mobile audio service data, mobile videoservice data, guide data, and so on. The secondary RS frame decoded bythe secondary RS frame decoder 117 outputs to the secondary RS framebuffer 132. The secondary RS frame buffer 132 buffers the secondary RSframe, and then configures an M/H TP in each row unit. The M/H TPs ofthe secondary RS frame outputs to the TP handler 133.

The TP handler 133 consists of a TP buffer and a TP parser. The TPhandler 133 buffers the M/H TPs inputted from the primary RS framebuffer 131 and the secondary RS frame buffer 132, and then extracts andanalyzes each header of the buffered M/H TPs, thereby recovering IPdatagram from each payload of the corresponding M/H TPs. The recoveredIP datagram is outputted to the IP datagram handler 141.

The IP datagram handler 141 consists of an IP datagram buffer and an IPdatagram parser. The IP datagram handler 141 buffers the IP datagramdelivered from the TP handler 133, and then extracts and analyzes aheader of the buffered IP datagram, thereby recovering UDP datagram froma payload of the corresponding IP datagram. The recovered UDP datagramis outputted to the UDP datagram handler 143.

If the UDP datagram is scrambled, the scrambled UDP datagram isdescrambled by the descrambler 142, and the descrambled UDP datagram isoutputted to the UDP datagram handler 143. For example, when the UDPdatagram among the received IP datagram is scrambled, the descrambler142 descrambles the UDP datagram by inputting an encryption key and soon from the service protection stream handler 146, and outputs thedescrambled UDP datagram to the UDP datagram handler 143.

The UDP datagram handler 143 consists of an UDP datagram buffer and anUDP datagram parser. The UDP datagram handler 143 buffers the UDPdatagram delivered from the IP datagram handler 141 or the descrambler142, and then extracts and analyzes a header of the buffered UDPdatagram, thereby recovering data transmitted through a payload of thecorresponding UDP datagram. If the recovered data is an RTP/RTCPdatagram, the recovered data is outputted to the RTP/RTCP datagramhandler 144. If the recovered data is also an NTP datagram, therecovered data is outputted to the NTP datagram handler 145.Furthermore, if the recovered data is a service protection stream, therecovered data is outputted to the service protection stream handler146. And, if the recovered data is an ALC/LCT stream, the recovered datais outputted to the ALC/LCT steam handler 148.

The IP datagram handler 141 and UDP datagram handler 143 can output dataincluding the SMT section data to the service signaling section handler123.

The RTP/RTCP datagram handler 144 consists of an RTP/RTCP datagrambuffer and an RTP/RTCP datagram parser. The RTP/RTCP datagram handler144 buffers the data of RTP/RTCP structure outputted from the UDPdatagram handler 143, and then extracts A/V stream from the buffereddata, thereby outputting the extracted A/V stream to the A/V decoder161.

The A/V decoder 161 decodes the audio and video streams outputted fromthe RTP/RTCP datagram handler 144 using audio and video decodingalgorithms, respectively. The decoded audio and video data is outputtedto the presentation manager 170. Herein, at least one of an AC-3decoding algorithm, an MPEG 2 audio decoding algorithm, an MPEG 4 audiodecoding algorithm, an AAC decoding algorithm, an AAC+ decodingalgorithm, an HE AAC decoding algorithm, an AAC SBR decoding algorithm,an MPEG surround decoding algorithm, and a BSAC decoding algorithm canbe used as the audio decoding algorithm and at least one of an MPEG 2video decoding algorithm, an MPEG 4 video decoding algorithm, an H.264decoding algorithm, an SVC decoding algorithm, and a VC-1 decodingalgorithm can be used as the audio decoding algorithm.

The NTP datagram handler 145 consists of an NTP datagram buffer and anNTP datagram parser. The NTP datagram handler 145 buffers data having anNTP structure, the data being outputted from the UDP datagram handler143. Then, the NTP datagram handler 145 extracts an NTP stream from thebuffered data. Thereafter, the extracted NTP stream is outputted to theA/V decoder 161 so as to be decoded.

The service protection stream handler 146 may further include a serviceprotection stream buffer. Herein, the service protection stream handler146 buffers data designated (or required) for service protection, thedata being outputted from the UDP datagram handler 143. Subsequently,the service protection stream handler 146 extracts required informationfor descrambling from the extracted data. The information required fordescrambling includes a key value, such as STKM and LTKM. Theinformation for descrambling is stored in the second storage unit 147,and, when required, the information for descrambling is outputted to thedescrambler 142.

The ALC/LCT stream handler 148 consists of an ALC/LCT stream buffer andan ALC/LCT stream parser. And, the ALC/LCT stream handler 148 buffersdata having an ALC/LCT structure, the data being outputted from the UDPdatagram handler 143. Then, the ALC/LCT stream handler 148 analyzes aheader and a header expansion of an ALC/LCT session from the buffereddata. Based upon the analysis result of the header and header expansionof the ALC/LCT session, when the data being transmitted to the ALC/LCTsession correspond to an XML structure, the corresponding data areoutputted to an XML parser 150. Alternatively, when the data beingtransmitted to the ALC/LCT session correspond to a file structure, thecorresponding data are outputted to a file decoder 162. At this point,when the data that are being transmitted to the ALC/LCT session arecompressed, the compressed data are decompressed by a decompressor 149,thereby being outputted to the XML parser 150 or the file decoder 162.

If the data transferred through the ALC/LCT session is compressed, thedecompressor 149 decompresses the transferred data and outputs thedecompressed data to the file decoder 162.

The FDT handler 151 analyzes and processes a file description table of aFLUTE protocol, which is transmitted in an XML structure through theALC/LCT session.

The SG handler 165 collects and analyzes the data designated for aservice guide, the data being transmitted in an XML structure, therebyoutputting the analyzed data to the service manager 122.

The file decoder 162 decodes the data having a file structure and beingtransmitted through the ALC/LCT session, thereby outputting the decodeddata to the middleware engine 164 or storing the decoded data in a thirdstorage unit 163. Herein, the middleware engine 164 translates the filestructure data (i.e., the application) and executes the translatedapplication. Thereafter, the application may be outputted to an outputdevice, such as a display screen or speakers, through the applicationpresentation manager 170. According to an embodiment of the presentinvention, the middleware engine 164 corresponds to a JAVA-basedmiddleware engine.

Based upon a user-input, the EPG manager 171 receives EPG data eitherthrough the service manager 122 or through the SG handler 165, so as toconvert the received EPG data to a display format, thereby outputtingthe converted data to the presentation manager 170.

The application manager 172 performs overall management associated withthe processing of application data, which are being transmitted inobject formats, file formats, and so on. Furthermore, based upon auser-command inputted through the UI manager 173, the operationcontroller 100 controls at least one of the service manager 122, the EPGmanager 171, the application manager 172, and the presentation manager170, so as to enable the user-requested function to be executed. The UImanager 173 transfers the user-input to the operation controller 100through the UI.

Finally, the presentation manager 170 provides at least one of the audioand video data being outputted from the A/V decoder 161 and the EPG databeing outputted from the EPG manager 171 to the user through the speakerand/or display screen.

Regarding the present invention, the NRT service is included the mobilebroadcast service. The NRT service is signaled by the SMT section. Inthis case, the SMT section, for example, is extracted from the primaryRS frame decoder 116 or the second RS frame decoder 117. The extractedSMT section data is processed by IP module through the IP adaptationmodule. At this time, the IP datagram including the extracted SMTsection is processed by IP datagram handler 141. And the UDP datagram isprocessed by the UDP datagram handler 143. The UDP datagram handler 143extracts the SMT section data from the processed UDP datagram. Theextracted SMT section data is processed by service signaling sectionhandler 123. Moreover, the FDT data and the NRT service data except theSMT section data may provide an NRT service processed by the mobilebroadcast receiver through ALC/LCT processor.

A Structure of Data Format for the Mobile NRT Service

Meanwhile, the data structure used in the mobile broadcasting technologyaccording to the embodiment of the present invention may include a datagroup structure and an RS frame structure, which will now be describedin detail.

FIG. 20 illustrates an exemplary structure of a data group according tothe present invention. FIG. 20 shows an example of dividing a data groupaccording to the data structure of the present invention into 10 M/Hblocks (i.e., M/H block 1 (B1) to M/H block 10 (B10)). In this example,each M/H block has the length of 16 segments. Referring to FIG. 20, onlythe RS parity data are allocated to portions of the 5 segments beforethe M/H block 1 (B1) and the 5 segments following the M/H block 10(B10). The RS parity data are excluded in regions A to D of the datagroup. More specifically, when it is assumed that one data group isdivided into regions A, B, C, and D, each M/H block may be included inany one of region A to region D depending upon the characteristics ofeach M/H block within the data group.

Herein, the data group is divided into a plurality of regions to be usedfor different purposes. More specifically, a region of the main servicedata having no interference or a very low interference level may beconsidered to have a more resistant (or stronger) receiving performanceas compared to regions having higher interference levels. Additionally,when using a system inserting and transmitting known data in the datagroup, wherein the known data are known based upon an agreement betweenthe transmitting system and the receiving system, and when consecutivelylong known data are to be periodically inserted in the mobile servicedata, the known data having a predetermined length may be periodicallyinserted in the region having no interference from the main service data(i.e., a region wherein the main service data are not mixed). However,due to interference from the main service data, it is difficult toperiodically insert known data and also to insert consecutively longknown data to a region having interference from the main service data.

Referring to FIG. 20, M/H block 4 (B4) to M/H block (B7) correspond toregions without interference of the main service data. M/H block 4 (B4)to M/H block 7 (B7) within the data group shown in FIG. 20 correspond toa region where no interference from the main service data occurs. Inthis example, a long known data sequence is inserted at both thebeginning and end of each M/H block. In the description of the presentinvention, the region including M/H block 4 (B4) to M/H block 7 (B7)will be referred to as “region A (=B4+B5+B6+B7)”. As described above,when the data group includes region A having a long known data sequenceinserted at both the beginning and end of each M/H block, the receivingsystem is capable of performing equalization by using the channelinformation that can be obtained from the known data. Therefore, thestrongest equalizing performance may be yielded (or obtained) from oneof region A to region D.

In the example of the data group shown in FIG. 20, M/H block 3 (B3) andM/H block 8 (B8) correspond to a region having little interference fromthe main service data. Herein, a long known data sequence is inserted inonly one side of each M/H block B3 and B8. More specifically, due to theinterference from the main service data, a long known data sequence isinserted at the end of M/H block 3 (B3), and another long known datasequence is inserted at the beginning of M/H block 8 (B8). In thepresent invention, the region including M/H block 3 (B3) and M/H block 8(B8) will be referred to as “region B (=B3+B8)”. As described above,when the data group includes region B having a long known data sequenceinserted at only one side (beginning or end) of each M/H block, thereceiving system is capable of performing equalization by using thechannel information that can be obtained from the known data. Therefore,a stronger equalizing performance as compared to region C/D may beyielded (or obtained).

Referring to FIG. 20, M/H block 2 (B2) and M/H block 9 (B9) correspondto a region having more interference from the main service data ascompared to region B. A long known data sequence cannot be inserted inany side of M/H block 2 (B2) and M/H block 9 (B9). Herein, the regionincluding M/H block 2 (B2) and M/H block 9 (B9) will be referred to as“region C (=B2+B9)”. Finally, in the example shown in FIG. 20, M/H block(B1) and M/H block 10 (B10) correspond to a region having moreinterference from the main service data as compared to region C.Similarly, a long known data sequence cannot be inserted in any side ofM/H block 1 (B1) and M/H block 10 (B10). Herein, the region includingM/H block 1 (B1) and M/H block 10 (B10) will be referred to as “region D(=B1+B10)”. Since region C/D is spaced further apart from the known datasequence, when the channel environment undergoes frequent and abruptchanges, the receiving performance of region C/D may be deteriorated.

Additionally, the data group includes a signaling information areawherein signaling information is assigned (or allocated). In the presentinvention, the signaling information area may start from the 1^(st)segment of the 4^(th) M/H block (B4) to a portion of the 2^(nd) segment.According to an embodiment of the present invention, the signalinginformation area for inserting signaling information may start from the1^(st) segment of the 4^(th) M/H block (B4) to a portion of the 2^(nd)segment. More specifically, 276(=207+69) bytes of the 4^(th) M/H block(B4) in each data group are assigned as the signaling information area.In other words, the signaling information area consists of 207 bytes ofthe 1^(st) segment and the first 69 bytes of the 2^(nd) segment of the4^(th) M/H block (B4). The 1^(st) segment of the 4^(th) M/H block (B4)corresponds to the 17^(th) or 173^(rd) segment of a VSB field.

Herein, the signaling data transmitted through the signaling informationarea may be identified by two different types of signaling channel data:a transmission parameter channel (TPC) data and a fast informationchannel (FIC) data.

Also, the TPC data includes parameters that are mostly used in aphysical layer module. And, since the TPC data are transmitted withoutbeing interleaved, the TPC data may be accessed by slot unit in thereceiving system. The FIC data are provided in order to enable thereceiving system to perform fast service acquisition. Herein, the FICdata include cross layer information between a physical layer and anupper layer. The FIC data are interleaved in sub-frame units and thentransmitted.

For example, when the data group includes 6 known data sequences, asshown in FIG. 20, the signaling information area is located between thefirst known data sequence and the second known data sequence. Morespecifically, the first known data sequence is inserted in the last 2segments of the 3^(rd) M/H block (B3), and the second known datasequence in inserted in the 2^(nd) and 3^(rd) segments of the 4^(th) M/Hblock (B4). Furthermore, the 3^(rd) to 6^(th) known data sequences arerespectively inserted in the last 2 segments of each of the 4^(th),5^(th), 6^(th), and 7^(th) M/H blocks (B4, B5, B6, and B7). The 1^(st)and 3^(rd) to 6^(th) known data sequences are spaced apart by 16segments.

A RS Frame Including the Mobile NRT Service

FIG. 21 is a view showing the structure of an RS frame containing amobile NRT service configured according to an embodiment of the presentinvention.

The RS frame is received for each M/H frame in a condition where thereceiving system is switched to a time-slicing mode. Each RS frameincludes IP streams of each mobile service data or signaling data, andservice map table (SMT) section data may exist in all RS frames. The SMTsection data may be an IP stream type, or a different data type. The RSframe data is allocated to region corresponding to a plurality of datagroups, and transmitted to a receiving system.

The RS frame according to the embodiment of the present inventionconsists of at least one M/H transport packet (TP). Herein, the M/H TPincludes an M/H header and an M/H payload.

The M/H payload may include mobile service data as well as signalingdata. More specifically, an M/H payload may include only mobile servicedata, or may include only signaling data, or may include both mobileservice data and signaling data. In this case, the mobile service datacan include an NRT service according to the present invention.

Also, when the M/H TP includes a second M/H header, this indicates thatthe M/H payload includes both the signaling data and the mobile servicedata. Finally, when M/H TP includes a third M/H header, this indicatesthat the M/H payload includes only the mobile service data. In theexample shown in FIG. 21, the RS frame is assigned with an IP datagram(IP datagram 1) for a SMT and IP datagrams (IP datagram 2 and IPdatagram 3) for two service types.

A Structure of Transmission Data

FIG. 22 is a view showing an example of a structure of an M/H frame fortransmitting and receiving mobile service data according to the presentinvention.

In the example shown in FIG. 22, one M/H frame consists of 5 sub-frames,wherein each sub-frame includes 16 slots. In this case, the M/H frameaccording to the present invention includes 5 sub-frames and 80 slots.Also, in a packet level, one slot is configured of 156 data packets(i.e., transport stream packets), and in a symbol level, one slot isconfigured of 156 data segments. Herein, the size of one slotcorresponds to one half (½) of a VSB field. More specifically, since one207-byte data packet has the same amount of data as a data segment, adata packet prior to being interleaved may also be used as a datasegment. At this point, two VSB fields are grouped to form a VSB frame.

Meanwhile, the mobile service data within one RS frame may be assignedeither to all of regions A/B/C/D within the corresponding data group, orto at least one of regions A/B/C/D. In the embodiment of the presentinvention, the mobile service data within one RS frame may be assignedeither to all of regions A/B/C/D, or to at least one of regions A/B andregions C/D. If the mobile service data are assigned to the latter case(i.e., one of regions A/B and regions C/D), the RS frame being assignedto regions A/B and the RS frame being assigned to regions C/D within thecorresponding data group are different from one another.

According to the embodiment of the present invention, the RS frame beingassigned to regions A/B within the corresponding data group will bereferred to as a “primary RS frame”, and the RS frame being assigned toregions C/D within the corresponding data group will be referred to as a“secondary RS frame”, for simplicity. Also, the primary RS frame and thesecondary RS frame form (or configure) one parade. More specifically,when the mobile service data within one RS frame are assigned either toall of regions A/B/C/D within the corresponding data group, one paradetransmits one RS frame. Conversely, when the mobile service data withinone RS frame are assigned either to at least one of regions A/B andregions C/D, one parade may transmit up to 2 RS frames. Morespecifically, the RS frame mode indicates whether a parade transmits oneRS frame, or whether the parade transmits two RS frames. Such RS framemode is transmitted as the TPC data. Table 4 below shows an example ofthe RS frame mode. The following Table 4 is an exemplary diagram for theRS frame mode.

TABLE 4 RS frame mode (2 bits) Description 00 There is only one primaryRS frame for all group regions 01 There are two separate RS frames.Primary RS frame for group regions A and B Secondary RS frame for groupregions C and D 10 Reserved 11 Reserved

Table 4 illustrates an example of allocating 2 bits in order to indicatethe RS frame mode. For example, referring to Table 1, when the RS framemode value is equal to ‘00’, this indicates that one parade transmitsone RS frame. And, when the RS frame mode value is equal to ‘01’, thisindicates that one parade transmits two RS frames, i.e., the primary RSframe and the secondary RS frame. More specifically, when the RS framemode value is equal to ‘01’, data of the primary RS frame for regionsA/B are assigned and transmitted to regions A/B of the correspondingdata group. Similarly, data of the secondary RS frame for regions C/Dare assigned and transmitted to regions C/D of the corresponding datagroup.

As described in the assignment of data groups, the parades are alsoassigned to be spaced as far apart from one another as possible withinthe sub-frame. Thus, the receiving system can be capable of respondingpromptly and effectively to any burst error that may occur within asub-frame. Furthermore, the method of assigning parades may beidentically applied to all M/H frames or differently applied to each M/Hframe. According to the embodiment of the present invention, the paradesmay be assigned differently for each M/H frame and identically for allsub-frames within an M/H frame. More specifically, the M/H framestructure may vary by M/H frame units. Thus, an ensemble rate may beadjusted on a more frequent and flexible basis.

That is, the concept of an M/H ensemble is applied in the embodiment ofthe present invention, thereby defining a collection (or group) ofservices. Each M/H ensemble carries the same QoS and is coded with thesame FEC code. Also, each M/H ensemble has the same unique identifier(i.e., ensemble ID) and corresponds to consecutive RS frames.

FIG. 23 illustrates a data transmission structure in a physical layeraccording to an embodiment of the present invention. More specifically,FIG. 23 shows an example of FIC data being included in each data groupand transmitted. As described above, an M/H frame for approximately0.968 seconds is divided into 5 sub-frames, wherein data groupscorresponding to multiple ensembles exist in combination within eachsub-frame. Also, the data groups corresponding to each ensemble areinterleaved in M/H frame units, so as to configure an RS frame belongingto one ensemble. In FIG. 23, 2 ensembles (wherein NoG=4 and NoG=3) existin each sub-frame. Furthermore, a predetermined portion (e.g., 37bytes/data group) of each data group is used for the purpose ofseparately delivering encoded FIC data apart from the RS frame datachannel. The FIC region assigned to each data group consists of one FICsegment. Herein, each of the FIC segments is interleaved in sub-frameunits. For example, RS-encoding and SCCC encoding processes are appliedto the RS frame data, and RS encoding and PCCC encoding processes areapplied to the FIC data. Also, as well as the FIC data, the RS encodingand PCCC encoding processes are applied to the TPC data. Morespecifically, (187+P,187)-RS encoding process is applied to the RS framedata, (51,37)-RS encoding process is applied to the FIC data, and(18,10)-RS encoding process is applied to the TPC. Herein, P is thenumber of parity bytes.

A Service Map Table (SMT)

Next, signaling information of NRT services transmitted through the IPdatagram in the RS frame of FIG. 21 will be described. Hereinafter, theSMT, which is one type of signaling information, will be described.

FIGS. 24 and 25 are views showing the bit-stream syntax of an SMTconfigured according to an embodiment of the present invention.

In FIGS. 24 and 25, shown an example that the SMT is written in an MPEGformat, by which the present invention is non-limited. Alternatively,the SMT can be defined in a different format.

The SMT describes service information and IP access information in anensemble in which the SMT is transmitted, and also provides broadcaststream information of a service using Transport_Stream_ID which is anidentifier of a broadcast stream to which each service belongs. The SMTaccording to the present embodiment contains description information ofeach mobile service in a single MH ensemble, and other supplementaryinformation may be contained in a descriptor section.

Referring to FIGS. 24 and 25, an SMT section may be transmitted in astate of being included in an RS frame in an IP stream format. In thiscase, the RS frame decoders of the below-described receiver decode aninput RS frame and output the decoded RS frame to RS frame handlers.Each of the RS frame handlers divides the input RS frame into rows,configures an MH TP, and outputs the MH TP to an MH TP handler.

An example of the fields that may be transmitted through the SMT willnow be described.

A table_id file is an 8-bit unsigned integer number that indicates thetype of table section being defined in Service Map Table (SMT).

A section_syntax_indicator field (1-bit) shall be set to ‘0’ to alwaysindicate that this table is derived from the short form of the MPEG-2private section table.

A private_indicator field (1-bit) shall be set to ‘1’.

A section_length field (12-bit) specifies the number of remaining bytesthis table section immediately following this field. The value in thisfield shall not exceed 4093 (‘0xFFD’).

A table_id_extension field (16-bit) is table-dependent. It shall beconsidered to be logically part of the table_id field providing thescope for the remaining fields. Herein, the table_id_extension field mayinclude a SMT_protocol_version field.

A SMT_protocol_version field is an 8-bit unsigned integer field whosefunction is to allow, in the future, this SMT to carry parameters thatmay be structured differently than those defined in the currentprotocol. At present, the value for the SMT_protocol_version shall bezero. Non-zero values of SMT_protocol_version may be used by a futureversion of this standard to indicate structurally different tables.

An ensemble_id field is an 8-bit unsigned integer field in the range0x00 to 0x3F shall be the Ensemble ID associated with this MH Ensemble.The value of this field shall be derived from the parade_id carried fromthe baseband processor of MH physical layer subsystem, by using theparade_id of the associated MH Parade for the least significant 7 bits,and using ‘0’ for the most significant bit when the MH Ensemble iscarried over the Primary RS frame, and using ‘1’ for the mostsignificant bit when the MH Ensemble is carried over the Secondary RSframe.

A version_number field (5 bits) represents version number of the SMT.

A current_next_indicator field is a one-bit indicator, which when set to‘1’ shall indicate that the Service Map Table sent is currentlyapplicable. When the bit is set to ‘0’, it shall indicate that the tablesent is not yet applicable and will be the next table to become valid.This standard imposes no requirement that next tables (those withcurrent_next_indicator set to ‘0’) must be sent. An update to thecurrently applicable table shall be signaled by incrementing theversion_number field.

A section_number field (8-bit) shall give the section number of this NRTService Signaling table_section. The section_number of the first sectionin an NRT Service Signaling table shall be ‘0x00’. The section_numbershall be incremented by 1 with each additional section in the NRTService Signaling table.

A last_section_number field (8-bit) shall give the number of the lastsection (i.e., the section with the highest section_number) of theService Signaling table of which this section is a part.

A num_services field (8 bit) specifies the number of services in thisSMT section.

According to one embodiment of the present invention, the NST providesinformation for a plurality of components using ‘for’ loop. Fieldinformation related to each service is provided as follows.

A service_id is a 16-bit unsigned integer number that shall uniquelyidentify this M/H Service within the scope of this MH Broadcast. TheMH_service_id of a service shall not change throughout the life of theservice. To avoid confusion, it is recommended that if a service isterminated, then the MH_service_id for the service should not be usedfor another service until after a suitable interval of time has elapsed.

A multi_ensemble_service field is a two-bit enumerated field that shallidentify whether the M/H Service is carried across more than one M/HEnsemble. Also, this field shall identify whether or not the M/H Servicecan be rendered only with the portion of M/H Service carried throughthis M/H Ensemble.

A MH_service_status field is a 2-bit enumerated field that shallidentify the status of this M/H Service. The most significant bit shallindicate whether this M/H Service is active (when set to ‘1’) orinactive (when set to ‘0’) and the least significant bit shall indicatewhether this M/H Service is hidden (when set to ‘1’) or not (when set to‘0’). Hidden services are normally used for proprietary applications,and ordinary receiving devices should ignore them.

A SP_indicator field (1-bit) indicate, when set, that service protectionis applied to at least one of the components needed to provide ameaningful presentation of this M/H Service.

A short_service_name_length field is a three-bit unsigned integer thatshall indicate the number of byte pairs in the short_service_name field.This value is shown as m in the No. of Bits column for theshort_service_name field. When there is no short name of this M/Hservice, the value of this field shall be ‘0’.

A short_service_name field is the short name of the M/H Service, eachcharacter of which shall be encoded. When there is an odd number ofbytes in the short name, the second byte of the last of the byte pairper the pair count indicated by the short_service_name_length fieldshall contain ‘0x00’.

A MH_service_category field is a 6-bit enumerated type field that shallidentify the type category of service carried in this M/H Service asdefined in Table 5. When the value of this field is set to the valuewhich is indicated Informative only, the value of this field shall betreated as an informative description to the category of service, andthe receiver is required to examine the component_level_descriptors( )of the SMT-MH to identify the actual category of service carried throughthis M/H Service. For services that have a video and/or audio component,they shall have an NTP timebase component.

TABLE 5 MH_service_category Meaning 0x00 The service category is notspecified by the MH_service_category field. Look in thecomponent_level_descriptors( ) to identify the category of service. 0x01Basic TV (Informative only) - Look in the component_level_descriptors( )to identify the specific category of service. 0x02 Basic Radio(Informative only) - Look in the component_level_descriptors( ) toidentify the specific category of service. 0x03 RI service - RightsIssuer service as defined in Part #6 [34] of this standard. 0x04 Notspecified by the current version of this standard. 0x05 Not specified bythe current version of this standard. 0x06 Not specified by the currentversion of this standard. 0x07 Not specified by the current version ofthis standard. 0x08 Service Guide - Service Guide (Announcement) asdefined in Part #4 [x] of this standard. 0x09 Not specified by thecurrent version of this standard. 0x0A Not specified by the currentversion of this standard. 0x0B~0x0D Not specified by the current versionof this standard. 0x0E NRT service 0x0F~0XFF Reserved for future use.

If the value of the field is, for example, ‘0x0E’, it can be seen thatthe mobile service is a mobile NRT service. Accordingly, the receiverdetermines that the mobile service is an NRT service if the value of theMH_ service_ category field is ‘0x0E’ and, as a result, should check thecomponent_descriptor of a component level containing information about aFLUTE session in which the identified NRT service is transmitted. In thechecking of component_descriptor, if the value of the component_typefield in the descriptor is ‘38’, information about the FLUTE sessionreceived by component data is extracted.

A num_components field (5-bit) specifies the number of IP streamcomponents in this M/H Service.

An IP_version_flag field is a 1-bit indicator, which when set to 0 shallindicate that source_IP_address, MH_service_destination_IP_address, andcomponent_destination_IP_address fields are IPv4 addresses. The value of1 for this field is reserved for possible future indication thatsource_IP_address, MH_service_destination_IP_address, andcomponent_destination_IP_address fields are for IPv6. Use of IPv6addressing is not currently defined.

A source_IP_address_flag field is a 1-bit Boolean flag that shallindicate, when set, that a source IP address value for this M/H Serviceis present to indicate a source specific multicast.

An MH_service_destination_IP_address_flag field is a 1-bit Boolean flagthat indicates, when set to 1, that a MH_service_destination_IP_addressvalue is present, to serve as the default IP address for the componentsof this M/H Service.

A source_IP_address field shall be present if the source_IP_address_flagis set to 1 and shall not be present if the source_IP_address_flag isset to 0. If present, this field shall contain the source IP address ofall the IP datagrams carrying the components of this M/H Service. Theconditional use of the 128 bit-long address version of this field is tofacilitate possible use of IPv6 in the future, although use of IPv6 isnot currently defined.

An MH_service_destination_IP_address field shall be present if theMH_service_destination_IP_address_flag is set to and shall not bepresent if the MH_service_destination_IP_address_flag is set to 0. Ifthis MH_service_destination_IP_address is not present, then thecomponent_destination_IP_address field shall be present for eachcomponent in the num_components loop. The conditional use of the 128bit-long address version of this field is to facilitate possible use ofIPv6 in the future, although use of IPv6 is not currently defined.

According to one embodiment of the present invention, the SMT providesinformation for a plurality of components using ‘for’ loop.

An essential_component_indicator field is a one-bit indicator which,when set to 1, shall indicate that this component is an essentialcomponent for the M/H Service. Otherwise, this field indicates that thiscomponent is an optional component.

A component_destination_IP_address_flag field is a 1-bit Boolean flagthat shall indicate, when set to 1, that thecomponent_destination_IP_address is present for this component.

A port_num_count field shall indicate the number of destination UDPports associated with this UDP/IP stream component. The values of thedestination UDP port numbers shall start from thecomponent_destination_UDP_port_num field and shall be incremented byone, except in the case of RTP streams, when the destination UDP portnumbers shall start from the component_estination_UPD_port_num field andshall be incremented by two, to allow for the RTCP streams associatedwith the RTP streams.

A component_destination_UDP_port_num field (16-bit unsigned integer)represents the destination UDP port number for this UDP/IP streamcomponent. For RTP streams, the value ofcomponent_estination_UDP_port_num shall be even, and the next highervalue shall represent the destination UDP port number of the associatedRTCP stream.

A component_destination_IP_address field shall be present if thecomponent_destination_IP_address_flag is set to and shall not be presentif the component_destination_IP_address_flag is set to 0. When thisfield is present, the destination address of the IP datagrams carryingthis component of the MH Service shall match the address in this field.When this field is not present, the destination address of the IPdatagrams carrying this component shall match the address in theMH_service_destination_IP_address field. The conditional use of the 128bit-long address version of this field is to facilitate possible use ofIPv6 in the future, although use of IPv6 is not currently defined.

A num_component_level_descriptors field (4 bit) specifies the number ofcomponent level descriptors for this component.

A component_level_descriptor( ) field may have one or more descriptorsproviding additional information for this IP stream component, may beincluded.

A num_MH_service_level_descriptors field (4 bit) specifies the number ofservice level descriptors for this service.

An MH_service_level_descriptor( ) has Zero or more descriptors providingadditional information for this M/H Service, may be included.

A num_ensemble_level_descriptors field (4 bit) specifies the number ofensemble level descriptors for this ensemble.

An ensemble_level_descriptor( ) is zero or more descriptors providingadditional information for the M/H Ensemble which this SMT-MH describes,may be included.

The Source_IP_address becomes a source IP address of the same server fortransmitting all the channels of the FLUTE session if the service is anNRT service.

The MH_service_destination_IP_Address is signaled if a destination IPaddress having the session level of this FLUTE session is present.

The component may be mapped to a channel in the FLUTE session, and aseparate destination IP address (different from an IP address signaledin the session units) may be signaled throughcomponent_destination_IP_address according to channels. In addition, adestination port number may be signaled throughcomponent_destination_UDP_port_num, and the destination port numberstarted from component_destination_UDP_port_num may be further specifiedthrough port_num_count.

A Mobile NRT Service Signaling Architecture

The signaling of information about individual M/H NRT content items isdone at two levels: First, the File Delivery Table (FDT) of the FLUTEsessions used to deliver the items lists all the content items and givestheir sizes, data types, and other information relevant to theacquisition of the items. Second, the OMA BCAST Service Guide (SG) givesmore detailed descriptive information about the items and their deliveryschedules).

An NRT_component_descriptor( )

The contents included in the NRT service are transmitted via FLUTEsession. In this case, information related to the FLUTE session issignaled as follows by access information in the SMT.

Yet, NRT_component_descriptor( ) in a mobile service environment has thestructure similar to NRT_component_descriptor in a fixed serviceenvironment. The above-mentioned descriptions will be cited for thedescriptions of the same parts and differences will be mainly describedin the following description.

The FDT of the FLUTE sessions used to deliver the items lists all thecontent items and gives their sizes, data types, and other informationrelevant to the acquisition of the items.

For example, the receiver may configure and display a service guideusing an OMA BCAST SG. The receiver acquires information for accessing aFLUTE session in which content selected from the displayed service guideis transmitted. In addition, the receiver receives a file by mappinginformation about the transmitted file through the file information(FDT) in the accessed FLUTE session based on the access informationacquired from the SMT and content identifier of the OMA BCAST SG. Thecontent identifier of the OMA BCAST SG may contain globalContentID forglobally and uniquely identifying a content item using XML orNRT_content_id which is separately defined in association with an NRTservice, and conversion thereof is necessary for mapping with the fileinformation in the FLUTE session, which is the value of a binary type.The conversion process will be described in detail later and will beomitted herein.

In order to signal the FLUTE session, parameters are necessary. Suchparameters include necessary parameters and parameters which areselectively necessary in association with the FLUTE session. First, thenecessary parameters include a “source_IP_address” parameter, a “numberof channels_in the session” parameter, a “destination IP address andport number for each channel in the session” parameter, a “TransportSession Identifier (TSI) of the session” parameter and a “start time andend time of the session” parameter, and the parameters which areselectively necessary in association with the FLUTE session include an“FEC object transmission information” parameter, a “some informationthat tells receiver in the first place, that the session contains filesthat are of interest”, and a “bandwidth specification” parameter.

The “number of channels in the session” parameter may be explicitlyprovided or may be obtained by summing the number of streams configuringthe session. Among the parameters, the “start time and end time of thesession” parameter may be signaled through the SMT suggested by thepresent invention, and the “source IP address” parameter, the“destination IP address and port number for each channel in the session”parameter, the “Transport Session Identifier (TSI) of the session”parameter and the “number of channels in the session” parameter may besignaled through session_description_descriptor.

An NRT_component_data_descriptor for the Mobile NRT Service

If the value of the component_type field in the descriptor is ‘38’,information about the FLUTE session received by component data isextracted. Yet, NRT_component_descriptor( ) in a mobile serviceenvironment has the structure similar to NRT_component_descriptor in afixed service environment. The above-mentioned descriptions will becited for the descriptions of the same parts and differences will bemainly described in the following description.

The parameters are signaled by the FLUTE component data bytes.Accordingly, required information is provided to receive the FLUTEsession. In this case, the FDT is received through the received FLUTEsession. Moreover, information related to all files transferred throughthe FLUTE session is acquired from the received FDT. Therefore, the filecan be received based on the acquired information.

In this case, the NRT component descriptor may be transferred throughcomponent level descriptor loop in the SMT. Although there are aplurality of the FLUTE channel is, the TSI, the session_start_time,session_end_time and the like as parameters of the session level can besignaled by one time. At this time, NRT component descriptor can betransmitted through the component_level_descriptor loop in one componentamong a plurality of a channel component.

A Relationship Among M/H Service, FLUTE Session and NRT Service

FIG. 26 is a view explaining a relationship among an M/H service, aFLUTE session and an NRT service according to the present invention.

The M/H services include one or more M/H components. The FLUTE sessioncorresponds to an MH service component. And a relationship between theFLUTE session and the MH service component is defined throughMH_component_descriptor. In addition, a single M/H NRT service containsmultiple FLUTE sessions and each of the FLUTE sessions contains multipleFLUTE channels. The MH component may be defined by a single destinationIP address and a single UDP port number. For example, an MH NRT serviceA includes a FLUTE session 1, the FLUTE session 1 is indicated by TSI 1information of an MH component 1 and an MH component 2 of the MHservices. In addition, an MH NRT service B contains FLUTE sessions 2 and3. The FLUTE session 2 is indicated by TSI 2 information of an MHcomponent 3 and an MH component 4 of the MH services, and the FLUTEsession 3 is indicated by TSI 3 information of an MH component 5.

A Method for Processing Additional Information Related to a Service or aContent in the NRT Service

Embodiments for a method of processing the NRT service in a receiveraccording to the present invention are explained in the followingdescription. In this case, the NRT service may include additionalinformation related to the service or the content. And, the additionalinformation related to the service or the content may include logoinformation, icon information and so on (hereinafter, for convenience ofdescription, ‘logo’).

Moreover, with the exception of specially defined cases, the NRT serviceaccording to the present invention may be transceived (transmitted andreceived) by the above-mentioned fixed NRT service method and mobile NRTservice method.

Regarding the present invention, information related to the NRT servicemay be transceived using a variety of methods. In this case, theinformation related to the NRT service may include additionalinformation related to the service or the content. Moreover, the serviceor the content may be currently announced in the receiver. Theinformation related to the NRT service can be transceived by beingdefined as a pre-defined program information table. If the informationis included in the pre-defined program information table, theinformation may be defined in a descriptor format transmitted along withthe corresponding program information table. At this time, the firstembodiment can be applicable a fixed NRT service and a mobile NRTservice. In the following description, the pre-defined programinformation table will be referred to as a service map table (SMT) in amobile service environment for simplicity. And, also, the descriptor mayuse a descriptor of service level of the SMT. Yet, it is understood thatthe same principle is also applicable to a fixed service environment.

A download_image_descriptor in the SMT

FIG. 27 is an exemplary diagram for a bit-stream syntax of a descriptorincluded in the SMT according to the present invention. In the followingdescription, the descriptor will be referred to asdownload_image_descriptor (hereinafter, ‘DID’), for simplicity. Yet, thepresent invention will not be limited to the example given herein. Forinstance, the DID is included in a service level descriptor loop withinthe SMT.

Fields for configuring the DID are explained as follows. FIG. 27 showsan example of the DID being written in an MPEG format, the presentinvention will not be limited to the example given herein. And,therefore, the DID can be defined in a different format.

A descriptor_tag field has a value of ‘0xTBD’ to identify the DID.

A descriptor_length field represents a length of this descriptor.

A download_image_type field identifies a usage type of an imagedownloaded through the NRT service.

FIG. 28 is an exemplary diagram for information related to thedownload_image_type field.

Referring to the FIG. 28, the usage type or a format type of the imagedownloaded through the NRT service may include a broadcaster logo, achannel change image, a channel logo, a background image, a jointphotographic coding group (JPG), a graphics interchange format (GIF), abeep media player (BMP) and so on.

At this time, if a value of the download_image_type field is set to‘000’, there is the broadcaster logo which is the usage type of theimage downloaded through the NRT service. In this case, the broadcasterlogo can be used to an ensemble level. If a value of thedownload_image_type field is set to ‘001’, there is the channel changeimage which is the usage type of the image downloaded through the NRTservice. In this case, the channel change image can be used to a servicelevel. If a value of the download_image_type field is set to ‘010’,there is the channel logo which is a type of being used the imagedownloaded through the NRT service. In this case, the channel logo canbe used to a service level. If a value of the download_image_type fieldis set to ‘100’, there is the JPG which is a format type of being usedthe image downloaded through the NRT service. If a value of thedownload_image_type field is set to ‘101’, there is the GIF which is aformat type of being used the image downloaded through the NRT service.If a value of the download_image_type field is set to ‘110’, there isthe BMP which is a format type of being used the image downloadedthrough the NRT service. In this case, if a value of thedownload_image_type field is any one of ‘100’, ‘101’ and ‘110’, theimage can be used to a service level or a component level.

A content_id field includes an identifier for identifying a contentrelated to corresponding downloaded image.

A download_path_length field represents a length of the following thedownload_path field.

A download_path_type field identifies a type of a path to download animage. The type of the path, for example, is divided four types.Moreover, the path is specified to download the image using a text inaccordance with each type.

A download_path field represents the real text in accordance with thedownload_path_type field.

FIG. 29 is an exemplary diagram for specifying the download_path_typefield and the download_path field according to the present invention,and FIG. 30 is an exemplary diagram for representing a download path ofan image downloaded through a FLUTE session according to the presentinvention.

Referring to the FIG. 29, if a value of the download_path_type field isset to ‘00’, the image may be downloaded through a specific uniformresource locator (URL) (e.g., http://xxx.xxx.xx.xx (string)).

If a value of the download_path_type field is set to ‘01’, the image maybe downloaded through a DSM-CC (e.g.,dsmcc://ensemble_id/ipaddr:port/dsi_name_descriptor/dii_name_descriptor(string)).

If a value of the download_path_type field is set to ‘10’, the image maybe downloaded through a FLUTE session (e.g.,flute://ensemble_id/ipaddr:port/FDT_URI_Descriptor (string)). Referringto the FIG. 30, the FDT_URI_descriptor may represent a URI value relatedto location information of the image. Accordingly, the receiveridentifies an image downloaded through the FLUTE session based on thevalue of the FDT_URI.

If a value of the download_path_type field is set to ‘11’, the image maybe downloaded through a specific table.

In the following embodiments, a receiver, for example, receives andprocesses the additional information.

FIG. 31 is an exemplary flowchart for processing additional informationrelated to the announced service or content included the NRT serviceaccording to the present invention. In this case, the flowchart isspecified refer to the FIGS. 4 and 19.

1. In order to receive additional information relevant to the service orthe content, a receiver accesses a service signaling channel (SSC) viathe stream component handler or the IP module and then receives a SMTsection to receive the additional information related to the announcedservice or the announced content. In accessing the SSC, as mentioned inthe foregoing description, the receiver is able to use a well-known IPaddress and a well-known UDP port number.

2. The receiver receives and parses SMT section data received via theservice signaling section buffer/parser 217/123. First of all, thereceiver identifies the received service based on the parsed SMT sectiondata. At this time, the receiver is able to determine, for example,whether or not a received service is an NRT service based on theMH_service_ category field in the parsed SMT via the service manager122/228 or the NRT service manager 229.

3. If the corresponding service is an NRT service as a result of thedetermination in the above step 2 through the service manager 122/228 orthe NRT service manager 229, the receiver parses the DID from theservice level descriptor loop in the parsed SMT.

4. The receiver identifies a type of the image data and a format type ofthe image data based on the download_image_type field in the parsed DID.In this case, the image data can be transmitted through an NRT service.At this time, the type of the image data, for example, may include alogo, a background image and so on, shown by FIG. 29. Moreover, theimage file format, for example, may include the JPG, the GIF, the BMP,and so on, shown by FIG. 29.

5. Because the image data may be received along with A/V datatransmitted through the same NRT service, the receiver shall identifythe image data in the NRT service. In this case, the receiver can use anidentifier for identifying the image data based on the parsed DID. Forinstance, referring to the FIG. 29, the receiver uses the FDT_URIinformation received through the download_path field in the parsed DIDor the content_id information for identifying the image data from theA/V data file within the received service.

6. The receiver can extract FLUTE session information for receiving theimage data through the parsed SMT, receive the image data from theaccessed FLUTE session based on the extracted FLUTE session informationand store the received image data at file storage unit 163/225. In thiscase, the receiver may receive and store the image data using FLUTEsession information specified by the download_path field in the parsedDID.

7. The receiver controls to output the stored image data through an OnScreen Display (OSD) or a User Interface (UI) when the A/V data receivedthrough the corresponding service is reproduced. For instance, thecorresponding logo image is uploaded when the NRT service or MH servicehaving the service_id matched with the service_id of the correspondinglogo image is received. In this case, the logo image may be outputtedwhen the NRT service is reproduced. Or the logo image may be outputtedwhen the real time service is reproduced.

A download_image_descriptor in the NRT Content Table (NCT)

In the following description, the download_image_descriptor in the NCThas the structure similar to the DID in FIG. 27. The above-mentioneddescriptions in FIGS. 27 to 30 will be cited and omitted herein.

Yet, in the second embodiment, a case of defining information related tothe NRT service including additional information associated withannounced content into a descriptor format of a pre-defined programinformation table and then of transceiving the defined descriptor byhaving the descriptor included in the program information table will bedescribed in detail. In this case, the present embodiment is applicableto a fixed NRT service. Herein, the program information table includesthe NCT in a fixed environment for simplicity. And, also, the descriptormay use a descriptor on a content level of the NCT.

In the following embodiments, for example, a receiver receives andprocesses the additional information related to the announced content.

FIG. 32 is an exemplary flowchart for processing additional informationrelated to an announced content included in the NRT service according tothe present invention. In this case, the flowchart is specified refer tothe FIGS. 4 and 19.

1. For instance, referring to FIG. 9, in order to receive the additionalinformation relevant to the announced content, a receiver extracts PIDsand receives signaling data including the additional information basedon the extracted PIDs. In this case, the signaling information may be anNCT. And, the additional information, for example, includes webinformation related to the advanced electronic program guide (EPG).

2. The receiver receives and parses NCT section data received via theservice signaling section buffer/parser 217/123. In this case, thereceiver parses the DID from the content level descriptor loop in theparsed NCT.

3. The receiver reads the download_path field in the parsed DID. And,the receiver extracts URL information from the read download_path field.In this case, the receiver, for example, can be aware that download_pathfield includes the URL information if a value of the download_path fieldis set to ‘00’.

4. The receiver can connect an internet protocol (IP) based on theextracted URL information and receive the additional information relatedto the announced corresponding content through the connected IP. In thiscase, the additional information may include the logo image, the poster,and so on.

In the above-mentioned second embodiment, the additional informationrelated to the announced content is received through the connected IPbased on the extracted URL information. The present invention isparticularly efficient to transmit (enough) detail information relatedto the announced content when the bandwidth is not sufficient. Herein,according to the prevent invention, a transmission side only providesURL information of the additional information related to the announcedcontent and the reception side can receive the additional informationrelated to the announced content through the connected IP based on theprovided URL information from the transmission side.

FIGS. 33 and 34 are an exemplary diagram being displayed logo related tothe received service or content according to the present invention.

In this case, the FIG. 33 shows a logo for the announced NRT service.And, the FIG. 34 shows a logo for the announced content. At this time,the logo in the FIG. 34, for example, is a logo image of a real A/Vdata.

Referring to the FIGS. 33 and 34, the logo may be displayed at aspecific location in the screen. For instance, the location of thedisplayed logo is an upper end of a right side in the screen. Yet, thepresent invention will not be limited to the location. Herein, accordingto the present invention, the receiver can display the logo along withthe announced service or content.

Accordingly, the present invention provides the following effects and/oradvantages.

First of all, a transmitting end can have signaling data included toenable a receiver to appropriately recognize, receive and handle aprovided NRT service.

Secondly, a receiver properly receives and handles a received NRTservice using the transmitted signaling data and is then able to providethe handled service to a user.

Thirdly, a receiver is configured to provide a service guide to a userusing the transmitted signaling data.

Fourthly, a receiver is able to accurately receive and handle a contentselected from the configured service guide using the signalinginformation.

Finally, if additional information related to the announced service orcontent is included in a received NRT service, a receiver is able toproperly process the additional information.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A method of transmitting a broadcast signal for aNon Real Time (NRT) service, the method comprising: generating thebroadcast signal including the NRT service and signaling data includingan NRT Information Table (NRT-IT), the NRT Information Table describingone or more content items and signaling NRT service, signaling datafurther including a Service Map Table (SMT) containing service-levelattributes for the NRT broadcasting, wherein the SMT includesinformation used as a linkage to the NRT-IT; and transmitting the NRTservice via a broadcast channel and the signaling data via a ServiceSignaling Channel (SSC) with a specific IP address and UDP port number,wherein, the NRT service is delivered within IP packets, wherein the IPpackets are carried in MPEG-2 Transport Stream using Digital StorageMedia Command and Control (DSM-CC) Addressable Section format, whereinthe SMT includes a descriptor providing a reference to an image file ina File Delivery over Unidirectional Transport (FLUTE) file deliverysessions that is used as a service or content icon, wherein the imagefile containing an icon image and the reference corresponds to a FileDelivery Table (FDT) content linkage tag of the image file, wherein eachof FLUTE file delivery sessions includes one or more FLUTE channels, andwherein all of the FLUTE channels have a same IP address andconsecutively numbered UDP ports signaled with a single componentdescriptor in the SMT, wherein the NRT Information Table includeslinkage information matched with one or more files in one of FLUTE filedelivery sessions.
 2. The method of claim 1, wherein the NRT-IT includesfirst information representing a total size in bytes of the contentitem, second information specifying the content item title and thirdinformation specifying a length of the second information.
 3. The methodof claim 1, wherein the icon image is any one of a broadcaster logo, achannel change image, a channel logo, and a background image, and has animage format any one of JPEG and PNG.
 4. The method of claim 1, whereinthe SSC is carried in a portion of the IP packets.